Results 131 to 140 of about 22,374 (269)

ITA-JPN Broadband VLBI Experiment for Optical Clock Comparison [PDF]

, 2019
NICT has developed a broadband VLBI (very-long-baseline interferometry) system for intercontinental frequency transfer. After domestic tests in Japan, a 2.4 m diameter VLBI station was exported and installed at Medicina astronomy observatory of INAF in ...
Ujihara, H., Komuro, J., Pizzocaro, M., Bregolin, F., Levi, F., Cerretto, G., Mura, Alberto, Ishijima, H., Calonico, D., Ido, T., Sekido, M., Kawai, E., Cantoni, E., Nemitz, N., Okamoto, Y., Clivati, C., Tsutsumi, M., Namba, K., RICCI, ROBERTO, MACCAFERRI, GIUSEPPE, Hachisu, H., Takahashi, R., NEGUSINI, MONIA, Ichikawa, R., Takefuji, K., PERINI, FEDERICO   +25 more
core  

The Structure and Propagation of the Misaligned Jet M87

Galaxies, 2016
Due to its proximity, M87 is a prime target for next-generation high-resolution VLBI at short millimeter wavelengths, by which the jet launching region and the black hole shadow are expected to be resolved and imaged sometime soon.
Kazuhiro Hada
doaj   +1 more source

Estimating Integrated Water Vapor Trends From VLBI, GPS, and Numerical Weather Models: Sensitivity to Tropospheric Parameterization

Journal of Geophysical Research - Atmospheres, 2018
In this study, we estimate integrated water vapor (IWV) trends from very long baseline interferometry (VLBI) and global navigation satellite systems (GNSS) data analysis, as well as from numerical weather models (NWMs).
K. Balidakis, T. Nilsson, F. Zus, S. Glaser, R. Heinkelmann, Z. Deng, H. Schuh   +6 more
semanticscholar   +1 more source

Parallaxes and Proper Motions of Long Period Variable Stars Determined from VLBI and Gaia DR3

Galaxies
Annual 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, Tomoharu Kurayama, Hiroshi Sudou, Gabor Orosz   +3 more
doaj   +1 more source

Application of ray-traced tropospheric slant delays to geodetic VLBI analysis

Journal of Geodesy, 2017
The correction of tropospheric influences via so-called path delays is critical for the analysis of observations from space geodetic techniques like the very long baseline interferometry (VLBI).
A. Hofmeister, J. Böhm
semanticscholar   +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
core  

Solving the polarization problem in ALMA-VLBI observations [Elektronisk resurs]

, 2014
The Atacama Large mm-submm Array (ALMA) is, by far, the most sensitive mm/submm telescope in the World. The ALMA Phasing Project (APP) will allow us to phase-up all the ALMA antennas and use them as one single VLBI station.
Roy, A.,, Zensus, A.J.,, Conway, John,, Lindqvist, Michael,, Alef, W.,, Marti-Vidal, Ivan,   +5 more
core  

A VLBI receiving system for the South Pole Telescope

, 2018
The Event Horizon Telescope (EHT) is a very-long-baseline interferometry (VLBI) experiment that aims to observe supermassive black holes with an angular resolution that is comparable to the event horizon scale.
Laura Vertatschitsch, Reiland, George, Young, Andre, Evan Mayer, Antony A. Stark, Junhan Kim, Vertatschitsch, Laura, Sheperd S. Doeleman, Thomas W. Folkers, Carlstrom, John E., Kyle D. Massingill, Stark, Antony A., David Forbes, George Reiland, Jonathan Weintroub, Greer, Christopher H., Kim, Junhan, Jason SooHoo, Massingill, Kyle D., Weintroub, Jonathan, Lauria, Eugene F., Doeleman, Sheperd S., Beaudoin, Christopher, Christopher Beaudoin, Mayer, Evan, Chi H. Nguyen, Andre Young, Christopher H. Greer, Daniel P. Marrone, Eugene F. Lauria, Nguyen, Chi H., Marrone, Daniel P., Forbes, David, Folkers, Thomas W., John E. Carlstrom, SooHoo, Jason   +35 more
core   +1 more source

Effects of Earth’s Oblateness on Black Hole Imaging through Earth–Space and Space–Space Very Long Baseline Interferometry

The Astrophysical Journal
Earth-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, Ben Hudson, Daniel C. M. Palumbo   +2 more
doaj   +1 more source

Enhanced Stochastic Models for VLBI Invariant Point Estimation and Axis Offset Analysis

Remote Sensing
The 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
doaj   +1 more source