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Very Long Baseline Interferometry [PDF]

Highlights of Astronomy, 1989
The technique of very long baseline interferometry (VLBI) has undergone two decades of steady growth and refinement since its inception in 1967. In the beginning, only crude measurements of visibility on single baselines were possible. Now 18-station arrays have been used to produce images with dynamic ranges exceeding 2000:1; relative motions of ...
openaire   +2 more sources

A New Very Long Baseline Interferometry Method Based on the Uplink Signal

IEEE Access, 2020
Very long baseline interferometry (VLBI) is widely used for astronomical observations and navigation of deep space receivers. To solve the problems of the downlink signal being excessively weak to be received and the excessively large acquisition time, a
Linshan Xue, Weiren Wu, Xue Li
doaj   +1 more source

Selective Dynamical Imaging of Interferometric Data

The Astrophysical Journal Letters, 2022
Recent developments in very long baseline interferometry (VLBI) have made it possible for the Event Horizon Telescope (EHT) to resolve the innermost accretion flows of the largest supermassive black holes on the sky.
Joseph Farah, Peter Galison, Kazunori Akiyama, Katherine L. Bouman, Geoffrey C. Bower, Andrew Chael, Antonio Fuentes, José L. Gómez, Mareki Honma, Michael D. Johnson, Yutaro Kofuji, Daniel P. Marrone, Kotaro Moriyama, Ramesh Narayan, Dominic W. Pesce, Paul Tiede, Maciek Wielgus, Guang-Yao Zhao, The Event Horizon Telescope Collaboration, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Anne-Kathrin Baczko, David Ball, Mislav Baloković, John Barrett, Bradford A. Benson, Dan Bintley, Lindy Blackburn, Raymond Blundell, Wilfred Boland, Hope Boyce, Michael Bremer, Christiaan D. Brinkerink, Roger Brissenden, Silke Britzen, Avery E. Broderick, Dominique Broguiere, Thomas Bronzwaer, Sandra Bustamente, Do-Young Byun, John E. Carlstrom, Chi-kwan Chan, Koushik Chatterjee, Shami Chatterjee, Ming-Tang Chen, Yongjun Chen, Ilje Cho, Pierre Christian, John E. Conway, James M. Cordes, Thomas M. Crawford, Geoffrey B. Crew, Alejandro Cruz-Osorio, Yuzhu Cui, Jordy Davelaar, Mariafelicia De Laurentis, Roger Deane, Jessica Dempsey, Gregory Desvignes, Sheperd S. Doeleman, Ralph P. Eatough, Heino Falcke, Vincent L. Fish, Ed Fomalont, H. Alyson Ford, Raquel Fraga-Encinas, Per Friberg, Christian M. Fromm, Charles F. Gammie, Roberto Garc’a, Olivier Gentaz, Ciriaco Goddi, Roman Gold, Arturo I. Gómez-Ruiz, Minfeng Gu, Mark Gurwell, Kazuhiro Hada, Daryl Haggard, Michael H. Hecht, Ronald Hesper, Luis C. Ho, Paul Ho, Chih-Wei L. Huang, Lei Huang, David H. Hughes, Shiro Ikeda, Makoto Inoue, Sara Issaoun, David J. James, Buell T. Jannuzi, Michael Janssen, Britton Jeter, Wu Jiang, Alejandra Jimenez-Rosales, Svetlana Jorstad, Taehyun Jung, Mansour Karami, Ramesh Karuppusamy, Tomohisa Kawashima, Garrett K. Keating, Mark Kettenis, Dong-Jin Kim, Jae-Young Kim, Jongsoo Kim, Junhan Kim, Motoki Kino, Jun Yi Koay, Patrick M. Koch, Shoko Koyama, Carsten Kramer, Michael Kramer, Thomas P. Krichbaum, Cheng-Yu Kuo, Tod R. Lauer, Sang-Sung Lee, Aviad Levis, Yan-Rong Li, Zhiyuan Li, Rocco Lico, Greg Lindahl, Michael Lindqvist, Jun Liu, Kuo Liu, Elisabetta Liuzzo, Wen-Ping Lo, Andrei P. Lobanov, Laurent Loinard, Colin Lonsdale, Ru-Sen Lu, Nicholas R. MacDonald, Jirong Mao, Nicola Marchili, Sera Markoff, Alan P. Marscher, Iván Martí-Vidal, Satoki Matsushita, Lynn D. Matthews, Lia Medeiros, Karl M. Menten, Izumi Mizuno, Yosuke Mizuno, James M. Moran, Monika Moscibrodzka, Cornelia Müller, Alejandro Mus Mejas, Gibwa Musoke, Hiroshi Nagai, Neil M. Nagar, Masanori Nakamura, Gopal Narayanan, Iniyan Natarajan, Antonios Nathanail, Joey Neilsen, Roberto Neri, Chunchong Ni, Aristeidis Noutsos, Michael A. Nowak, Hiroki Okino, Héctor Olivares, Gisela N. Ortiz-León, Tomoaki Oyama, Feryal zel, Daniel C. M. Palumbo, Jongho Park, Nimesh Patel, Ue-Li Pen, Vincent Piétu, Richard Plambeck, Aleksandar PopStefanija, Oliver Porth, Felix M. Pötzl, Ben Prather, Jorge A. Preciado-López, Dimitrios Psaltis, Hung-Yi Pu, Venkatessh Ramakrishnan, Ramprasad Rao, Mark G. Rawlings, Alexander W. Raymond, Luciano Rezzolla, Bart Ripperda, Freek Roelofs, Alan Rogers, Eduardo Ros, Mel Rose, Arash Roshanineshat, Helge Rottmann, Alan L. Roy, Chet Ruszczyk, Kazi L. J. Rygl, Salvador Sánchez, David Sánchez-Arguelles, Mahito Sasada, Tuomas Savolainen, F. Peter Schloerb, Karl-Friedrich Schuster, Lijing Shao, Zhiqiang Shen, Des Small, Bong Won Sohn, Jason SooHoo, He Sun, Fumie Tazaki, Alexandra J. Tetarenko, Remo P. J. Tilanus, Michael Titus, Kenji Toma, Pablo Torne, Efthalia Traianou, Tyler Trent, Sascha Trippe, Ilse van Bemmel, Huib Jan van Langevelde, Daniel R. van Rossum, Jan Wagner, Derek Ward-Thompson, John Wardle, Jonathan Weintroub, Norbert Wex, Robert Wharton, Kaj Wiik, George N. Wong, Qingwen Wu, Doosoo Yoon, André Young, Ken Young, Ziri Younsi, Feng Yuan, Ye-Fei Yuan, J. Anton Zensus, Shan-Shan Zhao   +234 more
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Inverse MultiView. II. Microarcsecond Trigonometric Parallaxes for Southern Hemisphere 6.7 GHz Methanol Masers G232.62+00.99 and G323.74–00.26

The Astrophysical Journal, 2023
We present the first results from the Southern Hemisphere Parallax Interferometric Radio Astrometry Legacy Survey: 10 μ as accurate parallaxes and proper motions for two Southern Hemisphere 6.7 GHz methanol masers obtained using the inverse MultiView ...
L. J. Hyland, M. J. Reid, G. Orosz, S. P. Ellingsen, S. D. Weston, J. Kumar, R. Dodson, M. J. Rioja, W. J. Hankey, P. M. Yates-Jones, T. Natusch, S. Gulyaev, K. M. Menten, A. Brunthaler   +13 more
doaj   +1 more source

Single-band VLBI Absolute Astrometry

The Astronomical Journal, 2023
The ionospheric path delay impacts single-band, very long baseline interferometry (VLBI) group delays, which limits their applicability for absolute astrometry.
Leonid Petrov
doaj   +1 more source

Three-dimensional Orbit of AC Her Determined: Binary-induced Truncation Cannot Explain the Large Cavity in This Post-AGB Transition Disk

The Astrophysical Journal, 2023
Some evolved binaries, namely post–asymptotic giant branch (AGB) binaries, are surrounded by stable and massive circumbinary disks similar to protoplanetary disks found around young stars. Around 10% of these disks are transition disks: they have a large
Narsireddy Anugu, Jacques Kluska, Tyler Gardner, John D. Monnier, Hans Van Winckel, Gail H. Schaefer, Stefan Kraus, Jean-Baptiste Le Bouquin, Steve Ertel, Antoine Mérand, Robert Klement, Claire L Davies, Jacob Ennis, Aaron Labdon, Cyprien Lanthermann, Benjamin R. Setterholm, Theo ten Brummelaar, Akke Corporaal, Laurence Sabin, Jayadev Rajagopal   +19 more
doaj   +1 more source

Horizonless Spacetimes As Seen by Present and Next-generation Event Horizon Telescope Arrays

The Astrophysical Journal, 2023
We study the capabilities of present and future radio very long baseline interferometry arrays to distinguish black holes from horizonless spacetimes. We consider an example of a horizonless spacetime, obtained by overspinning a regular black hole.
Astrid Eichhorn, Roman Gold, Aaron Held
doaj   +1 more source

Key Science Goals for the Next-Generation Event Horizon Telescope

Galaxies, 2023
The Event Horizon Telescope (EHT) has led to the first images of a supermassive black hole, revealing the central compact objects in the elliptical galaxy M87 and the Milky Way.
Michael D. Johnson, Kazunori Akiyama, Lindy Blackburn, Katherine L. Bouman, Avery E. Broderick, Vitor Cardoso, Rob P. Fender, Christian M. Fromm, Peter Galison, José L. Gómez, Daryl Haggard, Matthew L. Lister, Andrei P. Lobanov, Sera Markoff, Ramesh Narayan, Priyamvada Natarajan, Tiffany Nichols, Dominic W. Pesce, Ziri Younsi, Andrew Chael, Koushik Chatterjee, Ryan Chaves, Juliusz Doboszewski, Richard Dodson, Sheperd S. Doeleman, Jamee Elder, Garret Fitzpatrick, Kari Haworth, Janice Houston, Sara Issaoun, Yuri Y. Kovalev, Aviad Levis, Rocco Lico, Alexandru Marcoci, Niels C. M. Martens, Neil M. Nagar, Aaron Oppenheimer, Daniel C. M. Palumbo, Angelo Ricarte, María  J. Rioja, Freek Roelofs, Ann C. Thresher, Paul Tiede, Jonathan Weintroub, Maciek Wielgus   +44 more
doaj   +1 more source

Demonstrating Photon Ring Existence with Single-baseline Polarimetry

The Astrophysical Journal Letters, 2023
Images of supermassive black hole accretion flows contain features of both curved spacetime and plasma structure. Inferring properties of the spacetime from images requires modeling the plasma properties, and vice versa.
Daniel C. M. Palumbo, George N. Wong, Andrew Chael, Michael D. Johnson   +3 more
doaj   +1 more source

The SFXC software correlator for Very Long Baseline Interferometry: Algorithms and Implementation [PDF]

, 2015
In this paper a description is given of the SFXC software correlator, developed and maintained at the Joint Institute for VLBI in Europe (JIVE). The software is designed to run on generic Linux-based computing clusters.
Calvés, G. Molera, Campbell, R. M., Cimó, G., Duev, D. A., Eldering, B., Keimpema, A., Kettenis, M. M., Kruithof, N., Marchal, D., Ozdemir, H., Paragi, Z., Pidopryhora, Y., Pogrebenko, S. V., Szomoru, A., van Langevelde, H. J., Yang, J.   +15 more
core   +2 more sources