Results 41 to 50 of about 810 (115)
Parallaxes and Proper Motions of Long Period Variable Stars Determined from VLBI and Gaia DR3
GalaxiesAnnual parallaxes of Galactic long period variable stars (LPVs) are essential for determining their distances and intrinsic properties, but their measurement remains challenging because of their large stellar sizes, circumstellar matter, and time ...
Akiharu Nakagawa +3 more
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The Astrophysical JournalEarth-based very long baseline interferometry (VLBI) has made rapid advances in imaging black holes. However, due to the limitations imposed on terrestrial VLBI by the Earth’s finite size and turbulent atmosphere, it is imperative to have a space-based ...
Aditya Tamar +2 more
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Enhanced Stochastic Models for VLBI Invariant Point Estimation and Axis Offset Analysis
Remote SensingThe accuracy and stability of Very Long Baseline Interferometry (VLBI) systems are essential for maintaining global geodetic reference frames such as the International Terrestrial Reference Frame (ITRF). This study focuses on the precise determination of
Chang-Ki Hong, Tae-Suk Bae
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On the Integration of VLBI Observations to GENESIS into Global VGOS Operations
Remote SensingThe upcoming European Space Agency (ESA) satellite mission GENESIS is an Earth-orbiting satellite carrying instruments of all four space geodetic techniques.
David Schunck +2 more
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Monitoring of multi-frequency polarization of gamma-ray bright AGNs
EPJ Web of Conferences, 2013 We started two observing programs with the Korean VLBI Network (KVN) monitoring changes in the flux density and polarization of relativistic jets in gamma-ray bright AGNs simultaneously at 22, 43, 86, 129 GHz.
Lee Sang-Sung +7 more
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Prospects of Detecting a Jet in Sagittarius A* with Very-long-baseline Interferometry
The Astrophysical JournalEvent Horizon Telescope (EHT) images of the horizon-scale emission around the Galactic center supermassive black hole Sagittarius A* (Sgr A*) favor accretion flow models with a jet component. However, this jet has not been conclusively detected.
Erandi Chavez +5 more
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Optimal distribution of VLBI transmitters in the Galileo space segment for frame ties. [PDF]
Earth Planets Space, 2023 Wolf H, Böhm J.
europepmc +1 more source
Automated Modeling with AAP-Imfit: Astrometry and Photometry via CASA
The Astrophysical JournalVery long baseline interferometry (VLBI) provides the highest-resolution radio intensity maps, crucial for detailed studies of compact sources like active galactic nuclei (AGNs) and their relativistic jets.
Alfredo Amador-Portes +5 more
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Astronomy & AstrophysicsContext. Our previous work identified a class of SDSS quasars with multiple Gaia detections, classifying them as candidates for various astrophysical systems, such as quasar–star pairs, dual quasars, and gravitationally lensed quasars.
Zhang Y. +7 more
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Estimation of Earth Rotation Parameters Based on BDS-3 and Discontinuous VLBI Observations
Remote SensingEarth rotation parameters (ERPs) are fundamental to geodetic and astronomical studies. With its high measurement accuracy and stability, the Very Long Baseline Interferometry (VLBI) plays an irreplaceable role in estimating the ERPs and maintaining the ...
Chenxiang Wang +3 more
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