Demonstration of Ultrawideband Polarimetry Using VLBI Exploration of Radio Astrometry (VERA)
Galaxies, 2022 We report on recent technical developments in the front- and back-ends for the four 20 m radio telescopes of the Japanese Very-Long-Baseline Interferometry (VLBI) project, VLBI Exploration of Radio Astrometry (VERA). We present a brief overview of a dual-
Yoshiaki Hagiwara +5 more
doaj +3 more sources
An Updated View of the Milky Way from Maser Astrometry
Universe, 2022 Astrometric observations of maser sources in the Milky Way, using the Very Long Baseline Interferometry (VLBI) technique, have been exploited to determine the spiral structure of our Galaxy. Several major spiral arms have now been pinpointed in the first
Katharina Immer, Kazi L. J. Rygl
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Software and Techniques for VLBI Data Processing and Analysis
Universe, 2022 Very-long-baseline interferometry (VLBI) is a challenging observational technique, which requires in-depth knowledge about radio telescope instrumentation, interferometry, and the handling of noisy data.
Michael Janssen +2 more
doaj +1 more source
Position and Proper Motion of Sagittarius A* in the ICRF3 Frame from VLBI Absolute Astrometry
The Astronomical Journal, 2023 Sagittarius A* (Sgr A*) is a strong, compact radio source believed to be powered by a supermassive black hole at the galactic center. Extinction by dust and gas in the galactic plane prevents observing it optically, but its position and proper motion ...
David Gordon +2 more
doaj +1 more source
Toward Microarcsecond Astrometry for the Innermost Wobbling Jet of the BL Lacertae Object OJ 287
The Astrophysical Journal Letters, 2023 The BL Lacertae object OJ 287 is a very unusual quasar producing a wobbling radio jet and some double-peaked optical outbursts with a possible period of about 12 yr for more than one century.
Xiaopeng Cheng +5 more
doaj +1 more source
The Million Quasars (Milliquas) Catalogue, v8
The Open Journal of Astrophysics, 2023 Announcing the final release, v8, of the Milliquas (Million Quasars) quasar catalogue which presents all published quasars to 30 June 2023, including quasars from the first releases of the Dark Energy Spectroscopic Instrument (DESI) and the SDSS-DR18 ...
Eric Wim Flesch
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Overview and Status of the International Celestial Reference Frame as Realized by VLBI
Universe, 2022 Accurate measurement of angular positions on the sky requires a well-defined system of reference that is realized with accessible objects. The purpose of this study is to review the international standard realization of such a system, the International ...
Aletha de Witt +3 more
doaj +1 more source
Dynamical masses of young stellar objects with the VLBA: DYNAMO-VLBA
Astronomy & AstrophysicsWe present results from a multi-epoch Very Long Baseline Array (VLBA) survey of compact radio sources in the Orion complex, conducted within both the DYNAMO–VLBA and GOBELINS projects.
Dzib Sergio A. +11 more
doaj +3 more sources
Masses and Densities of Dwarf Planet Satellites Measured with ALMA
The Planetary Science Journal, 2023 We have used the Atacama Large Millimeter/submillimeter Array to measure precise absolute astrometric positions and detect the astrometric wobble of dwarf planet Orcus and its satellite Vanth over a complete orbit.
Michael E. Brown, Bryan J. Butler
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Probing the Heart of Active Narrow-line Seyfert 1 Galaxies with VERA Wideband Polarimetry
The Astrophysical Journal, 2023 We explored the parsec-scale nuclear regions of a sample of radio-loud narrow-line Seyfert 1 galaxies (NLSy1s) using the VLBI Exploration of Radio Astrometry wideband (at a recording rate of 16 Gbps) polarimetry at 22 and 43 GHz.
Mieko Takamura +11 more
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