Results 51 to 60 of about 15,217 (172)

VLBI Astrometry [PDF]

Symposium - International Astronomical Union, 1994
VLBI is at present the most accurate technique for measuring radiosource positions and the only method capable of high precision for a reasonable number of sources. The applications of VLBI astrometry in stellar, Galactic and extra-Galactic regimes are reviewed.
openaire   +1 more source

Obtaining Local‐Tie Vectors From Short‐Baseline Interferometry Between Legacy S/X and VGOS Telescopes at Ny‐Ålesund

Radio Science, Volume 61, Issue 9, September 2026.
Abstract With the ongoing transition for geodetic Very Long Baseline Interferometry (VLBI) from the use of legacy S/X telescopes to the VLBI Global Observing System (VGOS), it is necessary to connect the new VGOS network to the existing legacy S/X telescopes.
Rebekka Handirk, Eskil Varenius, Tobias Nilsson, Karine Le Bail, Rubén Bolaño González, Susana Garcia‐Espada, Axel Meldahl, Thomas Gasmoe, Silje Agnes Grøslie Wennesland, Oddvar Bråvold Tangen, Halfdan Pascal Kierulf   +10 more
wiley   +1 more source

EVN e-VLBI detections of MAXI J1659-152 [PDF]

, 2010
We observed MAXI J1659-152 following its sub-millimeter and centimeter radio detections with the European VLBI Network (EVN) in real-time e-VLBI ...
Paragi, Zsolt, Taylor, G.B., Wijers, R.A.M.J., Kouveliotou, C., Garrett, M.A., Taylor, G., van der Horst, A.J., Woods, P.M., Paragi, Z., Ramirez Ruiz, E., Granot, J., Horst, A. van der, Wijers, R., Ramirez-Ruiz, E., Kuulkers, E., Gehrels, N., Woods, P., Garrett, M.   +17 more
core  

The Celestial Frame and the Weighting of the Celestial Pole Offsets in the Computation of VLBI-Based Corrections for the Main Lunisolar Nutation Terms

Sensors, 2021
Very long baseline interferometry (VLBI) is the only technique in space geodesy that can determine directly the celestial pole offsets (CPO). In this paper, we make use of the CPO derived from global VLBI solutions to estimate empirical corrections to ...
Víctor Puente, Marta Folgueira
doaj   +1 more source

Optical‐to‐Microcomb Stability Transfer for Ultrastable Timing and Microwave/Millimeter‐Wave Generation

Laser &Photonics Reviews, Volume 20, Issue 14, 22 July 2026.
This work demonstrates a high‐fidelity stability transfer from an optical reference to a high‐repetition‐rate microcomb using a mode‐locked laser bridge. By employing electro‐optic sampling timing detection, femtosecond‐level synchronization and 10−18‐level fractional frequency stability are achieved.
Changmin Ahn, Junyong Choi, Daewon Suk, Hansuek Lee, Jungwon Kim   +4 more
wiley   +1 more source

Optical frequency comb integration in radio telescopes: advancing signal generation and phase calibration

Light: Science & Applications
Very long baseline interferometry (VLBI) enables high-angular-resolution observations in astronomy and geodesy by synthesizing a virtual telescope with baselines spanning hundreds to thousands of kilometres. Achieving high instrumental phase stability in
Minji Hyun, Changmin Ahn, Junyong Choi, Jihoon Baek, Woosong Jeong, Do-Heung Je, Do-Young Byun, Jan Wagner, Myoung-Sun Heo, Taehyun Jung, Jungwon Kim   +10 more
doaj   +1 more source

Effects of Surface Errors of Antennas on Detection Performance of Space VLBI

Aerospace, 2022
This work investigates the effects of the surface errors of the satellite antenna on the detection performance of the space VLBI system. First, the relationship between the surface errors and the antenna gain loss is analyzed, and then the influence of ...
Yangyang Zhang, Huijie Liu, Xingfu Liu
doaj   +1 more source

Japanese VLBI Project — Vera [PDF]

Symposium - International Astronomical Union, 1988
The Japanese VLBI project VERA (VLBI for the Earth Rotation study and Astrometry) is being designed. It will be dedicated to regular monitoring of the Earth's rotation and astrometry. VERA will be composed of two antennas spanning about 2300km and a correlator of multi-station capability. The diameters of the antennas are 35m and 15m.
Mitsumi Fujishita, Tadayoshi Hara
openaire   +1 more source

MSWD: A Hybrid Machine‐Learning Framework for Slant Wet Delay Modeling

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 12, 28 June 2026.
Abstract Space geodetic techniques such as Global Navigation Satellite Systems (GNSS) and Very Long Baseline Interferometry (VLBI) are limited by direction‐dependent tropospheric delays, with slant wet delay (SWD) being the most variable component and a major error source.
Zhenyi Zhang, Benedikt Soja
wiley   +1 more source

РАДИОСТРУКТУРА ИСТОЧНИКА 1803÷784

Odessa Astronomical Publications, 2011
Results of processing of data of ground-space VLBI experiment titled V053 are presented. These observations were made in 1997 October with 10 antennas of American interferometer VLBA and with Japan space telescope VSOP (VLBI Space Orbit Program).
A. А. Чуприков
doaj   +1 more source