학술논문
Greenland Telescope (GLT) Project: 'A Direct Confirmation of Black Hole with Submillimeter VLBI'
Document Type
Working Paper
Author
Nakamura, M.; Algaba, J. -C.; Asada, K.; Chen, B.; Chen, M. -T.; Han, J.; Ho, P. H. P.; Hsieh, S. -N.; Huang, T.; Inoue, M.; Koch, P.; Kuo, C. -Y.; Martin-Cocher, P.; Matsushita, S.; Meyer-Zhao, Z.; Nishioka, H.; Nystom, G.; Pradel, N.; Pu, H. -Y.; Raffin, P.; Shen, H. -Y.; Tseng, C. -Y.; Team, the Greenland Telescope Project
Source
Subject
Language
Abstract
The GLT project is deploying a new submillimeter (submm) VLBI station in Greenland. Our primary scientific goal is to image a shadow of the supermassive black hole (SMBH) of six billion solar masses in M87 at the center of the Virgo cluster of galaxies. The expected SMBH shadow size of 40-50 $\mu$as requires superbly high angular resolution, suggesting that the submm VLBI would be the only way to obtain the shadow image. The Summit station in Greenland enables us to establish baselines longer than 9,000 km with ALMA in Chile and SMA in Hawaii as well as providing a unique $u$--$v$ coverage for imaging M87. Our VLBI network will achieve a superior angular resolution of about 20 $\mu$as at 350 GHz, corresponding to $\sim2.5$ times of the Schwarzschild radius of the supermassive black hole in M87. We have been monitoring the atmospheric opacity at 230 GHz since August. 2011; we have confirmed the value on site during the winter season is comparable to the ALMA site thanks to high altitude of 3,200 m and low temperature of $-50\degr$C. We will report current status and future plan of the GLT project towards our expected first light on 2015--2016.
Comment: 4 pages, 5 figures; to appear in the conference proceedings of "Innermost Regions of Relativistic Jets and Their Magnetic Fields", June 10-14, 2013, Granada, Spain
Comment: 4 pages, 5 figures; to appear in the conference proceedings of "Innermost Regions of Relativistic Jets and Their Magnetic Fields", June 10-14, 2013, Granada, Spain