# 230 GHz VLBI OBSERVATIONS OF M87: EVENT‐HORIZON‐SCALE STRUCTURE DURING AN ENHANCED VERY‐HIGH‐ENERGY γ ?> ‐RAY STATE IN 2012

@article{Akiyama2015230GV,
title={230 GHz VLBI OBSERVATIONS OF M87: EVENT‐HORIZON‐SCALE STRUCTURE DURING AN ENHANCED VERY‐HIGH‐ENERGY $\gamma$ ?> ‐RAY STATE IN 2012},
author={Kazunori Akiyama and Ru-Sen Lu and Vincent L. Fish and Sheperd S. Doeleman and Avery E. Broderick and Jason Dexter and Kazuhiro Hada and Motoki Kino and Hiroshi Nagai and Mareki Honma and Michael D. Johnson and Juan Carlos Algaba and Keiichi Asada and Christiaan D. Brinkerink and Raymond Blundell and Geoffrey C. Bower and Roger J. Cappallo and Geoffrey B. Crew and Matt Dexter and Sergio A. Dzib and Robert W. Freund and Per Friberg and Mark A. Gurwell and Paul T. P. Ho and Makoto Inoue and Thomas P. Krichbaum and Laurent Loinard and David Macmahon and Daniel P. Marrone and James M. Moran and Masanori Nakamura and Neil M. Nagar and Gisela N. Ortiz-L{\'e}on and Richard L. Plambeck and Nicolas Pradel and Rurik A. Primiani and Alan E. E. Rogers and Alan L. Roy and Jason SooHoo and J. Le'on Tavares and Remo P. J. Tilanus and Michael Titus and Jan Wagner and Jonathan Weintroub and Paul Yamaguchi and K. H. Young and Anton Zensus and Lucy M Ziurys},
journal={The Astrophysical Journal},
year={2015},
volume={807}
}
• Published 13 May 2015
• Physics
• The Astrophysical Journal
We report on 230 GHz (1.3 mm) very long baseline interferometry (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, we have acquired 230 GHz VLBI interferometric phase information on M87 through measurement of the closure phase on the triangle of long baselines. Most of the measured closure phases are consistent with 0° as expected by physically motivated models for 230 GHz…
• Physics
• 2015
We report on results from new high-sensitivity, high-resolution 86 GHz (3.5 mm) observations of the jet base in the nearby radio galaxy M87, obtained by the Very Long Baseline Array in conjunction
• Physics
• 2018
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
• 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 ∼50 μas “shadow” of the supermassive black hole at the
Event Horizon Telescope (EHT) observations at 230 GHz are combined with Very Long Baseline Interferometry (VLBI) observations at 86 GHz and high-resolution Hubble Space Telescope optical observations
• Physics
• 2016
M87 is arguably the best supermassive black hole (BH) to explore jet and/or accretion physics, due to its proximity and fruitful high-resolution multi-waveband observations. We model the
• Physics
• 2018
We study the centimeter- to millimeter-wavelength synchrotron spectrum of the core of the radio galaxy M 87 at ≲0.8 mas ~ 110 R s spatial scales using four years of fully simultaneous,
• Physics
• 2016
M87 is one of the nearest radio galaxies with a central Super-Massive Black Hole (SMBH) and a prominent relativistic jet. Due to its close distance to the observer and the large SMBH mass, the source
• Physics
• 2016
We report on the 1.6 GHz (18 cm) very long baseline interferometry (VLBI) observations of the unresolved, steady TeV source HESS J1943+213 located in the Galactic plane, performed with the European
• Physics
The Astrophysical Journal
• 2019
We present the calibration and reduction of Event Horizon Telescope (EHT) 1.3 mm radio wavelength observations of the supermassive black hole candidate at the center of the radio galaxy M87 and the
• Physics
The Astrophysical Journal
• 2019
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 the

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