Results 61 to 70 of about 22,374 (269)
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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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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The Short-Arc Precise Orbit Determination of GEO Satellites Using VLBI and Transfer Ranging
Remote Sensing, 2022 It is important for a geostationary Earth orbit (GEO) satellite to rapidly recover its orbit after a maneuver with short-arc precise orbit determination (POD).
Kai Nan +5 more
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Earth, Planets and Space, 2023 VLBI simulation studies are carried out to investigate the impact of any proposed station or strategy on the geodetic parameters, such as Earth Orientation Parameters (EOP) and Terrestrial Reference Frame (TRF). In general, such studies are performed for
Sujata Dhar +5 more
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The 40-yr History of 3C84 and Future Prospects with VLBI and ALMA
, 2023 3C 84 is the bright, nearby radio source that is associated with a giant elliptical galaxy NGC 1275 (z=0.0176). Thanks to its proximity and brightness, 3C 84 has been studied using VLBI extensively in the context of jet formation, mechanism of high ...
Nagai, Hiroshi
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International Astronomical Union Colloquium, 1990 AbstractVLBI observations using a satellite in earth orbit and ground antennas in Japan and Australia were conducted in 1986, 1987, and 1988. Sources were detected on space-ground baselines at both observing frequencies: 2.3 and 15 GHz. The coherence on space-ground baselines for 340 s was 90% at 2.3 GHz and 76% at 15 GHz.
openaire +1 more source
Calibration of ALMA as a Phased Array. ALMA Observations During the 2017 VLBI Campaign [PDF]
Publications of the Astronomical Society of the Pacific, 2019 We present a detailed description of the special procedures for calibration and quality assurance of Atacama Large Millimeter/submillimeter Array (ALMA) observations in Very Long Baseline Interferometry (VLBI) mode.
C. Goddi +16 more
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Extragalactic maser VLBI studies: past, present and future
, 2023 Since three decades, VLBI studies of extragalactic (water) maser sources have incontrovertibly proved that they are unique tools to derive fundamental physical quantities of the host galaxies.
Tarchi, Andrea
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A 20+ year overview of VLBI observations of the peculiar radio source 3C 84
, 2023 The super-massive black holes (SMBH) located at the centres of AGN often launch highly relativistic jets. The main jet launching scenarios are either due to magnetic field lines anchored to the accretion disk (Blandford & Payne 1982) or directly ...
Paraschos, Georgios Filippos
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, 2023 The emission from blazar jets extends over the entire electromagnetic spectrum, from the radio to the very-high-energy (VHE) gamma rays range. The VLBI technique characterizes the parsec-scale regions of blazar jets. VLBI observations, e.g.
Nanci, Cristina on behalf of the MAGIC collaboration
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