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The Demographics of Sagittarius A* X-ray Flares over 25 Years with Chandra
Zach Sumners, Nicole M. Ford, Daryl Haggard +10
We present the Chandra 25-year Sagittarius A* (Sgr A*) X-ray flare catalog: a systematic analysis of 6.8 Ms of Sgr A* monitoring spanning the Chandra X-ray Observatory's mission li…
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…
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…
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…
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…
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…
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…
Tracking X-ray Variability in Next Generation EHT LLAGN Targets
Nicole M. Ford, Michael Nowak, Venkatessh Ramakrishnan +4
We present a 5 month NICER X-ray monitoring campaign for two low luminosity active galactic nuclei (LLAGNs) -- NGC 4594 and IC 1459 -- with complementary Swift and NuSTAR observati…
Power of simultaneous X-ray and UV high-resolution spectroscopy for probing AGN outflows
Missagh Mehdipour, Laura W. Brenneman, Jon M. Miller +6
Black hole accretion in active galactic nuclei (AGN) is coupled to the evolution of their host galaxies. Outflowing winds in AGN can play an important role in this evolution throug…
Multistructured accretion flow of Sgr A* II: Signatures of a Cool Accretion Disk in Hydrodynamic Simulations of Stellar Winds
Mayura Balakrishnan, Christopher M. P. Russell, Lia Corrales +8
Hydrodynamic simulations of the stellar winds from Wolf-Rayet stars within the Galactic Center can provide predictions for the X-ray spectrum of supermassive black hole Sgr A*. Her…
Multistructured accretion flow of Sgr A* I: Examination of a RIAF model
Mayura Balakrishnan, Lia Corrales, Sera Markoff +8
The extreme low-luminosity supermassive black hole Sgr A* provides a unique laboratory in which to test radiatively inefficient accretion flow (RIAF) models. Previous fits to the q…
Chandra Study of the Proper Motion of HST-1 in the Jet of M87
Rameshan Thimmappa, Joey Neilsen, Daryl Haggard +2
The radio galaxy M87 is well known for its jet, which features a series of bright knots observable from radio to X-ray wavelengths. We analyze the X-ray image and flux variability…
Broadband Multi-wavelength Properties of M87 during the 2018 EHT Campaign including a Very High Energy Flaring Episode
J. C. Algaba, M. Balokovic, S. Chandra +738
The nearby elliptical galaxy M87 contains one of the only two supermassive black holes whose emission surrounding the event horizon has been imaged by the Event Horizon Telescope (…
Ordered magnetic fields around the 3C 84 central black hole
G. F. Paraschos, J. -Y. Kim, M. Wielgus +279
3C84 is a nearby radio source with a complex total intensity structure, showing linear polarisation and spectral patterns. A detailed investigation of the central engine region nec…
First M87 Event Horizon Telescope Results. IX. Detection of Near-horizon Circular Polarization
The Event Horizon Telescope Collaboration
Event Horizon Telescope (EHT) observations have revealed a bright ring of emission around the supermassive black hole at the center of the M87 galaxy. EHT images in linear polariza…
Polarimetric Geometric Modeling for mm-VLBI Observations of Black Holes
Freek Roelofs, Michael D. Johnson, Andrew Chael +4
The Event Horizon Telescope (EHT) is a millimeter very long baseline interferometry (VLBI) array that has imaged the apparent shadows of the supermassive black holes M87* and Sagit…
First Sagittarius A* Event Horizon Telescope Results. V. Testing Astrophysical Models of the Galactic Center Black Hole
The Event Horizon Telescope Collaboration
In this paper, we provide a first physical interpretation for the Event Horizon Telescope (EHT)'s 2017 observations of Sgr A*. Our main approach is to compare resolved EHT data at…
First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon
The Event Horizon Telescope Collaboration
Event Horizon Telescope (EHT) observations at 230 GHz have now imaged polarized emission around the supermassive black hole in M87 on event-horizon scales. This polarized synchrotr…