Publications (44)
Kilogauss magnetic field and jet dynamics in the quasar NRAO 530
Mikhail Lisakov, Svetlana Jorstad, Maciek Wielgus +12
The advancement of the Event Horizon Telescope has enabled the study of relativistic jets in active galactic nuclei down to sub-parsec linear scales even at high redshift. Quasi-si…
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…
Micro-arcsecond structure of Sagittarius A* revealed by high-sensitivity 86 GHz VLBI observations
Christiaan D. Brinkerink, Cornelia Müller, Heino D. Falcke +21
The compact radio source Sagittarius~A (Sgr~A)in the Galactic Center is the primary supermassive black hole candidate. General relativistic magnetohydrodynamical (GRMHD) si…
Comparison of Polarized Radiative Transfer Codes used by the EHT Collaboration
Ben S. Prather, Cora Prather, Jason Dexter +271
Interpretation of resolved polarized images of black holes by the Event Horizon Telescope (EHT) requires predictions of the polarized emission observable by an Earth-based instrume…
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…
Collimation of the relativistic jet in the quasar 3C 273
Hiroki Okino, Kazunori Akiyama, Keiichi Asada +32
The collimation of relativistic jets launched from the vicinity of supermassive black holes (SMBHs) at the centers of active galactic nuclei (AGN) is one of the key questions to un…
Resolving the inner parsec of the blazar J1924-2914 with the Event Horizon Telescope
Sara Issaoun, Maciek Wielgus, Svetlana Jorstad +27
The blazar J1924-2914 is a primary Event Horizon Telescope (EHT) calibrator for the Galactic Center's black hole Sagittarius A*. Here we present the first total and linearly polari…
The intrinsic structure of Sagittarius A* at 1.3 cm and 7 mm
Ilje Cho, Guang-Yao Zhao, Tomohisa Kawashima +63
Sagittarius A* (Sgr A*), the Galactic Center supermassive black hole (SMBH), is one of the best targets to resolve the innermost region of SMBH with very long baseline interferomet…
Expanding Sgr A* dynamical imaging capabilities with an African extension to the Event Horizon Telescope
Noemi La Bella, Sara Issaoun, Freek Roelofs +2
The Event Horizon Telescope (EHT) has recently published the first images of the supermassive black hole at the center of our Galaxy, Sagittarius A* (Sgr A*). Imaging Sgr A* is pla…
Multi-frequency Black Hole Imaging for the Next-Generation Event Horizon Telescope
Andrew Chael, Sara Issaoun, Dominic W. Pesce +4
The Event Horizon Telescope (EHT) has produced images of the plasma flow around the supermassive black holes in Sgr A* and M87* with a resolution comparable to the projected size o…
Monitoring the Morphology of M87* in 2009-2017 with the Event Horizon Telescope
Maciek Wielgus, Kazunori Akiyama, Lindy Blackburn +26
The Event Horizon Telescope (EHT) has recently delivered the first resolved images of M87*, the supermassive black hole in the center of the M87 galaxy. These images were produced…
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…
Key Science Goals for the Next-Generation Event Horizon Telescope
Michael D. Johnson, Kazunori Akiyama, Lindy Blackburn +42
The Event Horizon Telescope (EHT) has led to the first images of a supermassive black hole, revealing the central compact objects in the elliptical galaxy M87 and the Milky Way. Pr…
Gravitational Test Beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole
Dimitrios Psaltis, Lia Medeiros, Pierre Christian +185
The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new…
Imaging the event horizon of M87* from space on different timescales
Anastasia Shlentsova, Freek Roelofs, Sara Issaoun +2
The concept of a new space very long baseline interferometry system named the Event Horizon Imager (EHI) has been proposed to dramatically improve black hole imaging and provide pr…
Multifrequency Synthesis via CHIBI: Colorful Hierarchical Interferometric Bayesian Imaging
Erandi Chavez, Paul Tiede, Sara Issaoun +4
From magnetized plasma of relativistic jets to dust grains within protoplanetary disks, we study the emission mechanisms of radio sources via their rich spectral structure. Multifr…
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…
First M87 Event Horizon Telescope Results and the Role of ALMA
Ciriaco Goddi, Geoff Crew, Violette Impellizzeri +41
In April 2019, the Event Horizon Telescope (EHT) collaboration revealed the first image of the candidate super-massive black hole (SMBH) at the centre of the giant elliptical galax…
The Black Hole Explorer: Motivation and Vision
Michael D. Johnson, Kazunori Akiyama, Rebecca Baturin +65
We present the Black Hole Explorer (BHEX), a mission that will produce the sharpest images in the history of astronomy by extending submillimeter Very-Long-Baseline Interferometry…
Unravelling the Innermost Jet Structure of OJ 287 with the First GMVA+ALMA Observations
Guang-Yao Zhao, Jose L. Gomez, Antonio Fuentes +33
We present the first very-long-baseline interferometric (VLBI) observations of the blazar OJ287 carried out jointly with the Global Millimeter VLBI Array (GMVA) and the phased Atac…
EHT-HOPS pipeline for millimeter VLBI data reduction
Lindy Blackburn, Chi-kwan Chan, Geoffrey B. Crew +12
We present the design and implementation of an automated data calibration and reduction pipeline for very-long-baseline interferometric (VLBI) observations taken at millimeter wave…
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…
Prospects of Detecting a Jet in Sagittarius A* with VLBI
Erandi Chavez, Sara Issaoun, Michael D. Johnson +3
Event Horizon Telescope (EHT) images of the horizon-scale emission around the Galactic Center supermassive black hole Sagittarius A* (Sgr A*) favor accretion flow models with a jet…
Reference Array and Design Consideration for the next-generation Event Horizon Telescope
Sheperd S. Doeleman, John Barrett, Lindy Blackburn +26
We describe the process to design, architect, and implement a transformative enhancement of the Event Horizon Telescope (ngEHT). This program - the next-generation Event Horizon Te…
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…
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…
First frequency phase transfer from the 3 mm to the 1 mm band on an Earth-sized baseline
Sara Issaoun, Dominic W. Pesce, MarÃa J. Rioja +33
Frequency Phase Transfer (FPT) is a technique designed to increase coherence and sensitivity in radio interferometry by making use of the non-dispersive nature of the troposphere t…
The internal Faraday screen of Sagittarius A*
Maciek Wielgus, Sara Issaoun, Ivan Marti-Vidal +5
We report on 85-101 GHz light curves of the Galactic Center supermassive black hole, Sagittarius A* (Sgr A*), observed in April 2017 with the Atacama Large Millimeter/submillimeter…
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…
A search for pulsars around Sgr A* in the first Event Horizon Telescope dataset
Pablo Torne, Kuo Liu, Ralph P. Eatough +282
The Event Horizon Telescope (EHT) observed in 2017 the supermassive black hole at the center of the Milky Way, Sagittarius A* (Sgr A*), at a frequency of 228.1 GHz (=1.3 mm). T…
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…
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…
The Black Hole Explorer: Operating a Hybrid Observatory
Sara Issaoun, Kim Alonso, Kazunori Akiyama +16
We present a baseline science operations plan for the Black Hole Explorer (BHEX), a space mission concept aiming to confirm the existence of the predicted sharp ``photon ring" resu…
Enabling Transformational ngEHT Science via the Inclusion of 86 GHz Capabilities
Sara Issaoun, Dominic W. Pesce, Freek Roelofs +13
We present a case for significantly enhancing the utility and efficiency of the ngEHT by incorporating an additional 86 GHz observing band. In contrast to 230 or 345 GHz, weather c…
Millimeter light curves of Sagittarius A* observed during the 2017 Event Horizon Telescope campaign
Maciek Wielgus, Nicola Marchili, Ivan Marti-Vidal +28
The Event Horizon Telescope (EHT) observed the compact radio source, Sagittarius A* (Sgr A*), in the Galactic Center on 2017 April 5-11 in the 1.3 millimeter wavelength band. At th…
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…
Toward Optimisation of a Sub-Terahertz Spaceborne VLBI Mission
Ben Hudson, Leonid I. Gurvits, Daniel Palumbo +2
Very Long Baseline Interferometry (VLBI) provides the finest angular resolution of all astronomical observation techniques. However, observations with Earth-based instruments are a…
High Data Rate Laser Communications for the Black Hole Explorer
Jade Wang, Bryan Bilyeu, Don Boroson +14
The Black Hole Explorer (BHEX) is a mission concept that can dramatically improve state-of-the-art astronomical very long baseline interferometry (VLBI) imaging resolution by exten…
The Event Horizon Telescope Image of the Quasar NRAO 530
Svetlana Jorstad, Maciek Wielgus, Rocco Lico +27
We report on the observations of the quasar NRAO 530 with the Event Horizon Telescope (EHT) on 2017 April 5-7, when NRAO 530 was used as a calibrator for the EHT observations of Sa…
Atmospheric limitations for high-frequency ground-based VLBI
Dominic W. Pesce, Lindy Blackburn, Ryan Chaves +10
Very long baseline interferometry (VLBI) provides the highest-resolution images in astronomy. The sharpest resolution is nominally achieved at the highest frequencies, but as the o…
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…
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…
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…
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 resoluti…