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The Greenland Telescope (GLT)* and Submillimeter VLBI

A ‘water spout’ maser jet in S235AB-MIR
Parabolic Streamline of the Black Hole-driven Jet from ten to million gravitational radii in M87
Extreme jet ejections from the black hole X-ray binary V404 Cygni
Velocity Field of M87 jet
Velocity Field of M87 jet
VSOP image of M87 at 5 GHz
VSOP image of M87 at 5 GHz
Deep inside Perseus A — A Space VLBI telescope makes a sharp image of the forming black hole jets in the core of a radio galaxy
Resolving the Geometry of Innermost Relativistic Jets in Blazars
Image simulation of black hole shadow and jet
Image simulation of black hole shadow and jet
Image simulation of black hole shadow
Semi-analytical GRMHD jet model
Visualizing ray around a Kerr black hole
ASIAA Cluster for VLBI DiFX correlator.
The ALMA-NA prototype telescope at Socorro, New Mexico, with one of the JVLA antennas.
ASIAA radiometer in Eureka, Canada
ASIAA radiometer in Eureka, Canada
ASIAA radiometer in Eureka, Canada
Disassemble one of the ALMA prototype antennas for retrofitting and ready for the use of VLBI in submillimeter wavelength

One of the ultimate observation goals in astrophysics is to directly observe the immediate surrounding of a black hole with angular resolution comparable to its event horizon. Observing and imaging its event horizon would be extremely important because it would open a new window on the study of General Relativity in the strong field regime, accretion and outflow processes at the edge of a black hole, the existence of an event horizon, and fundamental black hole physics, e.g. spin.

ASIAA has access to Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, and the James Clerk Maxwell Telescope (JCMT) and the Submillimeter Array (SMA) in Hawaii, linked together as a VLBI system, a potential angular resolution of a few micro-arcseconds can be achieved. There are two supermassive black holes (SMBH) with apparent sizes large enough to resolve with VLBI at submillimeter (submm) wavelengths: SgrA* at the Galactic Center, and the nucleus of M87. ASIAA proposed to add a fourth telescope to form a triangle with these telescopes. The presence of these telescopes will enable imaging, which would not be possible with a single baseline consisting of the JCMT/SMA and ALMA.

The National Science Foundation (NSF) in the United States awarded the 12m ALMA-North America Vertex Prototype Telescope to a team led by the ASIAA and the Smithsonian Astrophysical Observatory (SAO) in 2011. We proposed to deploy the 12m Telescope to Greenland in order to pursue submm-VLBI. Given the presence of the South Pole Telescope (SPT) in South Pole, submm-VLBI can be done for the southern sky by combining the SPT with the JCMT/SMA and ALMA. For the northern sky, Summit Station at 3200m in Greenland in the Arctic Circle, would be the best location for submm-VLBI with the SMA and ALMA. We finished the construction of the 12-m telescope at Thule, Greenland, and now renamed the Greenland Telescope (GLT). .

* collaborating with Smithsonian Astrophysical Observatory, MIT Haystack Observatory, & National Radio Astronomy Observatory

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