# Detection of Intrinsic Source Structure at ~3 Schwarzschild Radii with Millimeter-VLBI Observations of SAGITTARIUS A*

@article{Lu2018DetectionOI,
title={Detection of Intrinsic Source Structure at ~3 Schwarzschild Radii with Millimeter-VLBI Observations of SAGITTARIUS A*},
author={Rusen S. Lu and Thomas P. Krichbaum and Alan L. Roy and Vincent L. Fish and Sheperd S. Doeleman and Michael D. Johnson and Kazunori Akiyama and Dimitrios Psaltis and Walter Alef and Keiichi Asada and Christopher Beaudoin and Alessandra Bertarini and Lindy Blackburn and Raymond Blundell and Geoffrey C. Bower and Christiaan D. Brinkerink and Avery E. Broderick and Roger J. Cappallo and Geoffrey B. Crew and Jason Dexter and Matt Dexter and Heino Falcke and Robert W. Freund and Per Friberg and Christopher H. Greer and Mark A. Gurwell and Paul T. P. Ho and Mareki Honma and Makoto Inoue and Junhan Kim and James W. Lamb and Michael Lindqvist and David Macmahon and Daniel P. Marrone and Iv'an Mart'i-Vidal and Karl M. Menten and James M. Moran and Neil M. Nagar and Richard Plambeck and Rurik A. Primiani and Alan E. E. Rogers and Eduardo Ros and Helge Rottmann and Jason SooHoo and Justin S. Spilker and Jordan M. Stone and Peter A. Strittmatter and Remo P. J. Tilanus and Michael Titus and Laura Vertatschitsch and Jan Wagner and Jonathan Weintroub and Melvyn Wright and Ken Young and J. Anton Zensus and Lucy M Ziurys},
journal={The Astrophysical Journal},
year={2018},
volume={859},
pages={60}
}
• R. Lu, +53 authors L. Ziurys
• Published 2018
• Physics
• The Astrophysical Journal
We report results from very long baseline interferometric (VLBI) observations of the supermassive black hole in the Galactic center, Sgr A*, at 1.3 mm (230 GHz). The observations were performed in 2013 March using six VLBI stations in Hawaii, California, Arizona, and Chile. Compared to earlier observations, the addition of the APEX telescope in Chile almost doubles the longest baseline length in the array, provides additional uv coverage in the N-S direction, and leads to a spatial resolution… Expand
51 Citations

#### Figures and Tables from this paper

The Size, Shape, and Scattering of Sagittarius A* at 86 GHz: First VLBI with ALMA
The Galactic center supermassive black hole Sagittarius A∗ (Sgr A∗) is one of the most promising targets to study the dynamics of black hole accretion and outflow via direct imaging with very longExpand
Metrics and Motivations for Earth–Space VLBI: Time-resolving Sgr A* with the Event Horizon Telescope
• Physics
• The Astrophysical Journal
• 2019
Very-long-baseline interferometry (VLBI) at frequencies above 230 GHz with Earth-diameter baselines gives spatial resolution finer than the ${\sim}50 \mu$as "shadow" of the supermassive black hole atExpand
Simulations of imaging the event horizon of Sagittarius A* from space
Context. It has been proposed that Very Long Baseline Interferometry (VLBI) at submillimeter waves will allow us to image the shadow of the black hole in the center of our Milky Way, Sagittarius A*Expand
Persistent Non-Gaussian Structure in the Image of Sagittarius A* at 86 GHz
Observations of the Galactic Center supermassive black hole Sagittarius A* (Sgr A*) with very long-baseline interferometry (VLBI) are affected by interstellar scattering along our line of sight. AtExpand
Polarimetric Properties of Event Horizon Telescope Targets from ALMA
We present the results from a full polarization study carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) during the first Very Long Baseline Interferometry (VLBI) campaign,Expand
Micro-arcsecond structure of Sagittarius A* revealed by high-sensitivity 86 GHz VLBI observations
The compact radio source Sagittarius~A$^*$ (Sgr~A$^*$)in the Galactic Center is the primary supermassive black hole candidate. General relativistic magnetohydrodynamical (GRMHD) simulations of theExpand
First M87 Event Horizon Telescope Results. II. Array and Instrumentation
The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to theExpand
Spatially resolved origin of millimeter-wave linear polarization in the nuclear region of 3C 84
We report results from a deep polarization imaging of the nearby radio galaxy 3C 84 (NGC 1275). The source was observed with the Global Millimeter VLBI Array (GMVA) at 86 GHz at an ultrahigh angularExpand
Resolving the Nuclear Radio Emission from M32 with the Very Large Array
• Physics
• 2020
The Local Group dwarf elliptical galaxy M32 hosts one of the nearest and most under-luminous super-massive black holes (SMBHs) ever known, offering a rare opportunity to study the physics ofExpand
A parameter survey of Sgr A* radiative models from GRMHD simulations with self-consistent electron heating
The Galactic centre black hole candidate Sgr A* is the best target for studies of low-luminosity accretion physics, including with near-infrared (NIR) and submillimetre wavelength long baselineExpand

#### References

SHOWING 1-10 OF 56 REFERENCES
1.3 mm Wavelength VLBI of Sagittarius A*: Detection of Time-variable Emission on Event Horizon Scales
Sagittarius A*, the ~4 × 10^6 M_⊙ black hole candidate at the Galactic center, can be studied on Schwarzschild radius scales with (sub)millimeter wavelength very long baseline interferometry (VLBI).Expand
FINE-SCALE STRUCTURE OF THE QUASAR 3C 279 MEASURED WITH 1.3 mm VERY LONG BASELINE INTERFEROMETRY
We report results from five day very long baseline interferometry observations of the well-known quasar 3C 279 at 1.3 mm (230 GHz) in 2011. The measured nonzero closure phases on triangles includingExpand
THE SUBMILLIMETER BUMP IN Sgr A* FROM RELATIVISTIC MHD SIMULATIONS
• Physics
• 2010
Recent high resolution observations of the Galactic center black hole allow for direct comparison with accretion disk simulations. We compare two-temperature synchrotron emission models fromExpand
Millimeter Flares and VLBI Visibilities from Relativistic Simulations of Magnetized Accretion Onto the Galactic Center Black Hole
• Physics
• 2009
The recent very long baseline interferometry (VLBI) observation of the Galactic center black hole candidate Sgr A* at 1.3 mm shows source structure on event-horizon scales. This detection enables aExpand
Persistent Asymmetric Structure of Sagittarius A* on Event Horizon Scales
The Galactic Center black hole Sagittarius A* (Sgr A*) is a prime observing target for the Event Horizon Telescope (EHT), which can resolve the 1.3 mm emission from this source on angular scalesExpand
Wisps in the Galactic center: Near-infrared triggered observations of the radio source Sgr A* at 43 GHz
Context. The compact radio and near-infrared (NIR) source Sagittarius A* (Sgr A*) associated with the supermassive black hole in the Galactic center was observed at 7 mm in the context of a NIRExpand
Imaging an Event Horizon: Mitigation of Scattering Toward Sagittarius A*
The image of the emission surrounding the black hole in the center of the Milky Way is predicted to exhibit the imprint of general relativistic (GR) effects, including the existence of a shadowExpand
Discovery of Substructure in the Scatter-Broadened Image of Sgr A*
• Physics
• 2014
We have detected substructure within the smooth scattering disk of the celebrated Galactic Center radio source Sagittarius A* (SgrA*). We observed this structure at 1.3 cm wavelength with the VeryExpand
230 GHz VLBI Observations of M87: Event-horizon-scale Structure during an Enhanced Very-high-energy γ--Ray State in 2012
We report on 230 GHz (1.3 mm) VLBI observations of M87 with the Event Horizon Telescope using antennas on Mauna Kea in Hawaii, Mt. Graham in Arizona and Cedar Flat in California. For the first time,Expand
ESTIMATING THE PARAMETERS OF SAGITTARIUS A*'s ACCRETION FLOW VIA MILLIMETER VLBI
• Physics
• 2008
Recent millimeter-VLBI observations of Sagittarius A* (Sgr A*) have, for the first time, directly probed distances comparable to the horizon scale of a black hole. This provides unprecedented accessExpand