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arXiv · 2410.07453

First Very Long Baseline Interferometry Detections at 870{\mu}m

Alexander W. Raymond·Sheperd S. Doeleman·Keiichi Asada·Lindy Blackburn·Geoffrey C. Bower·Michael Bremer·Dominique Broguiere·Ming-Tang Chen·Geoffrey B. Crew·Sven Dornbusch·Vincent L. Fish·Roberto García·Olivier Gentaz·Ciriaco Goddi·Chih-Chiang Han·Michael H. Hecht·Yau-De Huang·Michael Janssen·Garrett K. Keating·Jun Yi Koay·Thomas P. Krichbaum·Wen-Ping Lo·Satoki Matsushita·Lynn D. Matthews·James M. Moran·Timothy J. Norton·Nimesh Patel·Dominic W. Pesce·Venkatessh Ramakrishnan·Helge Rottmann·Alan L. Roy·Salvador Sánchez·Remo P. J. Tilanus·Michael Titus·Pablo Torne·Jan Wagner·Jonathan Weintroub·Maciek Wielgus·André Young·Kazunori Akiyama·Ezequiel Albentosa-Ruíz·Antxon Alberdi·Walter Alef·Juan Carlos Algaba·Richard Anantua·Rebecca Azulay·Uwe Bach·Anne-Kathrin Baczko·David Ball·Mislav Baloković·Bidisha Bandyopadhyay·John Barrett·Michi Bauböck·Bradford A. Benson·Dan Bintley·Raymond Blundell·Katherine L. Bouman·Hope Boyce·Roger Brissenden·Silke Britzen·Avery E. Broderick·Thomas Bronzwaer·Sandra Bustamante·John E. Carlstrom·Andrew Chael·Chi-kwan Chan·Dominic O. Chang·Koushik Chatterjee·Shami Chatterjee·Yongjun Chen·Xiaopeng Cheng·Ilje Cho·Pierre Christian·Nicholas S. Conroy·John E. Conway·Thomas M. Crawford·Alejandro Cruz-Osorio·Yuzhu Cui·Rohan Dahale·Jordy Davelaar·Mariafelicia De Laurentis·Roger Deane·Jessica Dempsey·Gregory Desvignes·Jason Dexter·Vedant Dhruv·Indu K. Dihingia·Sergio A. Dzib·Ralph P. Eatough·Razieh Emami·Heino Falcke·Joseph Farah·Edward Fomalont·Anne-Laure Fontana·H. Alyson Ford·Marianna Foschi·Raquel Fraga-Encinas·William T. Freeman·Per Friberg·Christian M. Fromm
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Abstract

The first very long baseline interferometry (VLBI) detections at 870$\mu$m wavelength (345$\,$GHz frequency) are reported, achieving the highest diffraction-limited angular resolution yet obtained from the surface of the Earth, and the highest-frequency example of the VLBI technique to date. These include strong detections for multiple sources observed on inter-continental baselines between telescopes in Chile, Hawaii, and Spain, obtained during observations in October 2018. The longest-baseline detections approach 11$\,$G$\lambda$ corresponding to an angular resolution, or fringe spacing, of 19$\mu$as. The Allan deviation of the visibility phase at 870$\mu$m is comparable to that at 1.3$\,$mm on the relevant integration time scales between 2 and 100$\,$s. The detections confirm that the sensitivity and signal chain stability of stations in the Event Horizon Telescope (EHT) array are suitable for VLBI observations at 870$\mu$m. Operation at this short wavelength, combined with anticipated enhancements of the EHT, will lead to a unique high angular resolution instrument for black hole studies, capable of resolving the event horizons of supermassive black holes in both space and time.

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Alexander W. Raymond, Sheperd S. Doeleman, Keiichi Asada, Lindy Blackburn, Geoffrey C. Bower, Michael Bremer, Dominique Broguiere, Ming-Tang Chen, Geoffrey B. Crew, Sven Dornbusch, Vincent L. Fish, Roberto García, Olivier Gentaz, Ciriaco Goddi, Chih-Chiang Han, Michael H. Hecht, Yau-De Huang, Michael Janssen, Garrett K. Keating, Jun Yi Koay, Thomas P. Krichbaum, Wen-Ping Lo, Satoki Matsushita, Lynn D. Matthews, James M. Moran, Timothy J. Norton, Nimesh Patel, Dominic W. Pesce, Venkatessh Ramakrishnan, Helge Rottmann, Alan L. Roy, Salvador Sánchez, Remo P. J. Tilanus, Michael Titus, Pablo Torne, Jan Wagner, Jonathan Weintroub, Maciek Wielgus, André Young, Kazunori Akiyama, Ezequiel Albentosa-Ruíz, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Rebecca Azulay, Uwe Bach, Anne-Kathrin Baczko, David Ball, Mislav Baloković, Bidisha Bandyopadhyay, John Barrett, Michi Bauböck, Bradford A. Benson, Dan Bintley, Raymond Blundell, Katherine L. Bouman, Hope Boyce, Roger Brissenden, Silke Britzen, Avery E. Broderick, Thomas Bronzwaer, Sandra Bustamante, John E. Carlstrom, Andrew Chael, Chi-kwan Chan, Dominic O. Chang, Koushik Chatterjee, Shami Chatterjee, Yongjun Chen, Xiaopeng Cheng, Ilje Cho, Pierre Christian, Nicholas S. Conroy, John E. Conway, Thomas M. Crawford, Alejandro Cruz-Osorio, Yuzhu Cui, Rohan Dahale, Jordy Davelaar, Mariafelicia De Laurentis, Roger Deane, Jessica Dempsey, Gregory Desvignes, Jason Dexter, Vedant Dhruv, Indu K. Dihingia, Sergio A. Dzib, Ralph P. Eatough, Razieh Emami, Heino Falcke, Joseph Farah, Edward Fomalont, Anne-Laure Fontana, H. Alyson Ford, Marianna Foschi, Raquel Fraga-Encinas, William T. Freeman, Per Friberg, Christian M. Fromm. 2024-10-09. First Very Long Baseline Interferometry Detections at 870{\mu}m. https://doi.org/10.3847/1538-3881%2Fad5bdb

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