Results 1 to 10 of about 33,024 (227)
Sphero-Conical Modeling for the Estimation of Very Long Baseline Interferometry Invariant Point [PDF]
Sensors, 2022 A geodetic reference frame is a fundamental element in geoinformation fields such as autonomous navigation and digital twins. The international terrestrial reference frame is established and maintained using several space-geodetic techniques, including ...
Tae-Suk Bae, Chang-Ki Hong
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Introduction to very-long-baseline interferometry [PDF]
Proceedings of the IEEE, 1973 Long-baseline interferometry achieves high resolution by using two or more widely separated radio telescopes and recording video signals on magnetic tapes, which are later brought together and cross-correlated.
Cohen, Marshall H.
core +3 more sources
The Transformational Power of Frequency Phase Transfer Methods for ngEHT
Galaxies, 2023 (Sub) mm VLBI observations are strongly hindered by limited sensitivity, with the fast tropospheric fluctuations being the dominant culprit. We predict great benefits from applying next-generation frequency phase transfer calibration techniques for the ...
María J. Rioja +2 more
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High-sensitivity Beamformed Observations of the Crab Pulsar's Radio Emission
The Astrophysical Journal, 2023 We analyzed four epochs of beamformed European VLBI Network data of the Crab Pulsar at 1658.49 MHz. With the high sensitivity resulting from resolving out the Crab Nebula, we are able to detect even the faint high-frequency components in the folded ...
Rebecca Lin, Marten H. van Kerkwijk
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The Astrophysical Journal, 2023 Studying a centi-parsec supermassive black hole binary (SMBHB) would allow us to explore a new parameter space in active galactic nuclei, and these objects are also potential sources of gravitational waves.
Wu Jiang +8 more
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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
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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 +234 more
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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 +13 more
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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
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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 +19 more
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