Results 31 to 40 of about 9,054 (229)
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
doaj +1 more source
Decoherence in LOFAR-VLBI beamforming [PDF]
Astronomy & Astrophysics, 2020 We show that the use of a superstation (a phased array created using multiple stations of an interferometric array) created in post-processing for LOFAR-VLBI observations introduces a direction-dependent loss of signal in the image. We show this effect using simulations and real data.
Bonnassieux E. +3 more
openaire +3 more sources
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
doaj +1 more source
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
core +1 more source
A Study on the Development of Playback Control Software for Mark5B VSI System [PDF]
Journal of Astronomy and Space Sciences, 2010 We developed the playback control software for a high-speed playback system which is a component of the Korea-Japan Joint VLBI Correlator (KJJVC). The Mark5B system, which is a recorder and playback system used in the Korean VLBI Network (KVN), has two
S. J. Oh +5 more
doaj +1 more source
Preparation of the VIRAC Radio Telescope RT-32 for e-VLBI Observations
Open Astronomy, 2013 A fully steerable parabolic antenna RT-32 with the mirror diameter 32 m owned by the Ventspils International Radio Astronomy Centre (VIRAC) is available for fundamental and applied research in radio astronomy.
Skirmante K. +3 more
doaj +1 more source
Symposium - International Astronomical Union, 2001 Space VLBI enables high angular resolution and high dynamic range imaging through an extension of ground-based VLBI. The TDRSS space VLBI experiments in the 1980s were followed by the first space VLBI imaging mission, VSOP, in the 1990s. The new century holds the promise of the VSOP-2 and ARISE missions, which aim for more sensitive, higher angular ...
openaire +1 more source
Astrometric Apparent Motion of High-redshift Radio Sources
The Astronomical Journal, 2023 Radio-loud quasars at high redshift ( z ≥ 4) are rare objects in the universe and rarely observed with Very Long Baseline Interferometry (VLBI). But some of them have flux density sufficiently high for monitoring of their apparent position.
Oleg Titov +12 more
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Ground Based VLBI Facilities - the European and Global VLBI Network [PDF]
, 2004 11 pages, 5 figures, lecture presented at the NATA ASI VLBI School, Oct 2001. To be published in "The Role of VLBI in Astrophysics, Astrometry and Geodesy", ed. F. Mantovani.
openaire +2 more sources
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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