Results 151 to 160 of about 27,573 (245)

Prospects of Detecting a Jet in Sagittarius A* with Very-long-baseline Interferometry

The Astrophysical Journal
Event 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, Sara Issaoun, Michael D. Johnson, Paul Tiede, Christian Fromm, Yosuke Mizuno   +5 more
doaj   +1 more source

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

On the Integration of VLBI Observations to GENESIS into Global VGOS Operations

Remote Sensing
The upcoming European Space Agency (ESA) satellite mission GENESIS is an Earth-orbiting satellite carrying instruments of all four space geodetic techniques.
David Schunck, Lucia McCallum, Guifré Molera Calvés   +2 more
doaj   +1 more source

Automated Modeling with AAP-Imfit: Astrometry and Photometry via CASA

The Astrophysical Journal
Very 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, Eva Palafox, Víctor M. Patiño-Álvarez, Vahram Chavushyan, Andrei P. Lobanov, Sergio A. Dzib   +5 more
doaj   +1 more source

A pilot very long baseline interferometry study of the SQUAB quasar sample featuring multiple Gaia detections

Astronomy & Astrophysics
Context. 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., An T., Ji X., Zheng Z., Liu Y., Wu Q., Lin R., Liao S.   +7 more
doaj   +1 more source

VLBI Astrometry

, 2003
Latex, 6 pages, 8 figures; Invited Review Talk at the ``ADeLA2002 - Astrometry in Latin America'' Conference, Araraquara - Sao Paulo, 2 - 5 September 2002, to be published in ADeLA Publications Series, Vol.
openaire   +2 more sources

Estimation of Earth Rotation Parameters Based on BDS-3 and Discontinuous VLBI Observations

Remote Sensing
Earth 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, Jizhang Sang, Xingxing Li, Pengfei Zhang   +3 more
doaj   +1 more source

Opportunities with VLBI Transmitters on Satellites

Abstract Very Long Baseline Interferometry (VLBI) transmitters on satellites are considered for future satellites of Global Navigation Satellite Systems (GNSS) as well as for the upcoming Genesis mission of the European Space Agency (ESA).
Böhm, J., Wolf, H.
openaire   +2 more sources

Deep Very Long Baseline Interferometry Constraints on Compact Radio Cores in Four Ultraluminous X-Ray Sources

The Astrophysical Journal
We present high-sensitivity very long baseline interferometry (VLBI) observations of four ultraluminous X-ray sources (ULXs): Holmberg II X-1, IC 342 X-1, NGC 6946 X-1, and NGC 925 X-1.
Ailing Wang, Hua Feng, Tao An, Yijia Zhang, Jun Yang, Roberto Soria, Lian Tao, Thomas Russell, Jing Guo, Liang Zhang   +9 more
doaj   +1 more source

Inter-comparison study of time and frequency transfer between VLBI and other techniques (GPS, ETS8(TCE), TW(DPN) and DMTD)

, 2011
We carried out the intercomparison ex- periments between VLBI and other techniques to show the capability of VLBI time and frequency transfer by using the current geodetic VLBI tech- nique and facilities as the summary of the exper- iments that we ...
Hama, S, Ichikawa, R, Hobiger, T, Tsuchiya, S, Takiguchi, H, Fujieda, M, Nakamura, M, Kimura, M, Nakagawa, F, Koyama, Y, Tabuchi, R, Aida, M, Amagai, J, Li, T, Ishii, A, Takahashi, Y, Kondo, T, Gotoh, T   +17 more
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