Results 11 to 20 of about 9,456 (175)
A Comparative Study of VTEC Estimates Derived From S/X VLBI and VGOS Observations
Space WeatherThe ionosphere, which strongly varies in time and space, is one of the largest error sources for microwave measurements, if not accounted for accurately.
Arno Rüegg +2 more
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The Astrophysical Journal Supplement Series, 2022 Abstract High-redshift radio sources provide plentiful opportunities for studying the formation and evolution of early galaxies and supermassive black holes. However, the number of known radio-loud active galactic nuclei (AGN) above redshift 4 is rather limited.
Máté Krezinger +9 more
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Modeling Nearby Low-Luminosity Active-Galactic-Nucleus Jet Images at All VLBI Scales
Galaxies, 2022 Relativistic jets from nearby low-luminosity active-galactic-nuclei (LLAGN) were observed by Very-Long Baseline Interferometry (VLBI) across many orders of magnitude in space, from milliparsec to sub-parsec scales, and from the jet base in the vicinity ...
Hung-Yi Pu +2 more
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Very long baseline interferometry: accuracy limits and relativistic tests [PDF]
Proceedings of the International Astronomical Union, 2009 AbstractWe present a review on relativistic effects and best estimates of the relativistic PPN parameter γ obtained by analysis of data from the International VLBI Service for Geodesy and Astrometry (IVS). Relativistic implications are also considered in view of the upcoming new generation VLBI System: VLBI2010.
Heinkelmann, R., Schuh, H.
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Very-long-baseline radio interferometry (VLBI) observations of gamma-ray blazars: results from millimeter-VLBI observations. [PDF]
Proceedings of the National Academy of Sciences, 1995 VLBI observations of the extremely gamma-bright blazar PKS 0528+134 at 8, 22, 43, and 86 GHz reveal a strongly bent one-sided-core jet structure with at least three moving and two apparently stationary jet components. At the highest observing frequencies the brightest and most compact jet component (the VLBI core) is unresolved with an upper limit to ...
T P, Krichbaum +5 more
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Rotation of Earth and determination of Earth orientation parameters [PDF]
Geodetski Glasnik, 2015 Earth's rotation and elements of the Earth's orientation, with emphasis on the determination of the parameters of the Earth's orientation were described.
Mirko Borisov +2 more
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An Updated View of the Milky Way from Maser Astrometry
Universe, 2022 Astrometric observations of maser sources in the Milky Way, using the Very Long Baseline Interferometry (VLBI) technique, have been exploited to determine the spiral structure of our Galaxy. Several major spiral arms have now been pinpointed in the first
Katharina Immer, Kazi L. J. Rygl
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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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Data Handling within the International VLBI Service
Data Science Journal, 2013 The International VLBI Service for Geodesy and Astrometry (IVS) is a globally operating service that coordinates and performs Very Long Baseline Interferometry (VLBI) activities through its constituent components.
Dirk Behrend
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HINOTORI and Its Perspectives in the Black-Hole Jet Study
Galaxies, 2023 Simultaneous multi-band very long baseline interferometry (VLBI) observations at millimeter wavelengths have huge potential for various science cases.
Toshihisa Tsutsumi +12 more
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