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Related papers: The East-Asian VLBI Network

200 papers

Interest in the topic of geodetic co-location in space and space ties has recently intensified within the geodetic community, particularly following the approval of the European Space Agency's (ESA) Genesis mission. From the perspective of…

Geophysics · Physics 2026-03-19 David Schunck , Lucia McCallum , Jamie McCallum , Tiege McCarthy

Less than $200$ radio-loud active galactic nuclei (AGN) are known above redshift $4$. Around $40$ of them have been observed at milliarcsecond (mas) scale resolution with very long baseline interferometry (VLBI) technique. Some of them are…

Over the past 3 years, Auckland University of Technology has established the first radio astronomical observatory in New Zealand, which, because of its remote geographic location, has quickly become a member of a number of international…

Geophysics · Physics 2011-11-04 Sergei Gulyaev , Tim Natusch , Stuart Weston , Peter Thomasson

A review is given on the current status and selected results from large VLBI surveys of compact extragalactic radio sources made between 13 cm and 3 mm wavelengths and covering the entire sky. More than 4200 objects are observed and imaged…

Astrophysics · Physics 2009-07-22 Y. Y. Kovalev

Active galactic nuclei (AGN) are known for irregular variability on all time scales, down to intra-day variability with relative variations of a few percent within minutes to hours. On such short timescales, unexplored territory, such as…

Astrophysics of Galaxies · Physics 2015-11-27 Taeseok Lee , Sascha Trippe , Junghwan Oh , Do-Young Byun , Bong-Won Sohn , Sang-Sung Lee

We present pc-scale images of ten Compact Symmetric Objects (CSO) candidates observed with the European VLBI network (EVN). Five radio sources have been observed at 1.6 GHz, and five more at 2.3/8.4 GHz, the latter subsample with the…

Astrophysics · Physics 2009-11-07 Liu Xiang , Carlo Stanghellini , Daniele Dallacasa , Zhang Haiyan

The VLTI Spectro Imager (VSI) was proposed as a second-generation instrument of the Very Large Telescope Interferometer providing the ESO community with spectrally-resolved, near-infrared images at angular resolutions down to 1.1…

We present the results of Very Long Baseline Interferometry (VLBI) observations using the phase reference technique to detect weak Active Galactic Nuclei (AGN) cores in the Virgo cluster. Our observations were carried out using the Korean…

Astrophysics of Galaxies · Physics 2015-11-12 Evangelia Tremou , Taehyun Jung , Aeree Chung , Bong Won Sohn

EAS arrays are survey instruments able to monitor continuously all the overhead sky. Their sensitivity in the sub-TeV/TeV energy domain cannot compete with that of Cherenkov telescopes, but the wide field of view (about 2 sr) is ideal to…

High Energy Astrophysical Phenomena · Physics 2019-04-04 G. Di Sciascio

We explore the processes that trigger local AGN and the role of these AGN in regulating star formation, using ~350 nearby galaxies observed by the mJy Imaging VLBA Exploration at 20cm (mJIVE) survey. The >10^7 K brightness temperature…

Astrophysics of Galaxies · Physics 2015-07-15 Sugata Kaviraj , Stanislav S. Shabala , Adam T. Deller , Enno Middelberg

We describe an "active" antenna system for HF/VHF (long wavelength) radio astronomy that has been successfully deployed 256-fold as the first station (LWA1) of the planned Long Wavelength Array. The antenna system, consisting of crossed…

The highest-redshift quasars are still rare and valuable objects for observational astrophysics and cosmology. They provide important constraints on the growth of the earliest supermassive black holes in the Universe, and information on the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-13 S. Frey , L. I. Gurvits , Z. Paragi , K. E. Gabanyi

We summarize the present status of VLBI experiments at 3 mm (86 GHz), 2 mm (129-150 GHz) and 1.3 mm (215-230 GHz). We present and discuss a new 3 mm VLBI map of M87 (Virgo A), which has a spatial resolution of only approx. 20 Schwarzschild…

Over the past few decades, our knowledge of jets produced by active galactic nuclei (AGN) has greatly progressed thanks to the development of very-long-baseline interferometry (VLBI). Nevertheless, the crucial mechanisms involved in the…

High Energy Astrophysical Phenomena · Physics 2017-11-22 B. Boccardi , T. P. Krichbaum , E. Ros , J. A. Zensus

A second generation near-term space VLBI mission, VSOP-2, is being planned for a launch in 2010 or soon after. The scientific objectives are very high angular resolution imaging of astrophysically exotic regions, including the cores, jets,…

Astrophysics · Physics 2007-05-23 H. Hirabayashi , Y. Murata , P. G. Edwards , Y. Asaki , N. Mochizuki , M. Inoue , T. Umemoto , S. Kameno , Y. Kono

Shanghai Astronomical Observatory has upgraded its DiFX cluster to 420 CPU cores and a 432-TB storage system at the end of 2014. An international network connection for the raw data transfer has also been established. The routine operations…

Instrumentation and Methods for Astrophysics · Physics 2018-04-16 Wu Jiang , Zhiqiang Shen , Fengchu Shu , Zhong Chen , Tianyu Jiang

Millimetre-VLBI is an important tool in AGN astrophysics, but it is limited by short atmospheric coherence times and poor receiver and antenna performance. We demonstrate a new kind of phase referencing for the VLBA, enabling us to increase…

Astrophysics · Physics 2007-05-23 E. Middelberg , A. L. Roy , R. C. Walker , H. Falcke , T. P. Krichbaum

We examine the processes triggering star formation and Active Galactic Nucleus (AGN) activity in a sample of 25 low redshift ($z<0.13$) gas-rich galaxy mergers observed at milli-arcsecond resolution with Very Long Baseline Interferometry as…

Astrophysics of Galaxies · Physics 2016-10-12 Stanislav Shabala , Adam Deller , Sugata Kaviraj , Enno Middelberg , Ross Turner , Yuan-Sen Ting , James Allison , Tim Davis

Radio-loud active galactic nuclei (AGN) with their jets pointed close to our line of sight constitute the majority of extragalactic $\gamma$-ray sources and significantly contribute to the radiation observed in the even higher energy…

High Energy Astrophysical Phenomena · Physics 2025-02-06 J. Kőmíves , K. É. Gabányi , S. Frey , Z. Paragi , T. An , E. Kun

Polarization of radio emission in extragalactic jets at a sub-milliarcsecond angular resolution holds important clues for understanding the structure of the magnetic field in the inner regions of the jets and in close vicinity of the…