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We present GASV, a novel Python-based software package specifically designed for the analysis of Very Long Baseline Interferometry (VLBI) data. Developed with ease of installation and user friendliness in mind, GASV supports both pipeline…

Instrumentation and Methods for Astrophysics · Physics 2026-02-05 Dang Yao , Yuan-wei Wu , Xu-hai Yang

We have developed a 230 and 345 GHz very-long-baseline interferometry (VLBI) receiver for the South Pole Telescope (SPT). With the receiver installed, the SPT has joined the global Event Horizon Telescope (EHT) array. The receiver optics…

Instrumentation and Methods for Astrophysics · Physics 2018-09-25 Junhan Kim , Daniel P. Marrone

The calibration of Very Long Baseline Interferometry (VLBI) data has long been a time consuming process. The Korean VLBI Network (KVN) is a simple array consisting of three identical antennas. Because four frequencies are observed…

Instrumentation and Methods for Astrophysics · Physics 2017-08-23 Jeffrey A. Hodgson , Sang-Sung Lee , Guang-Yao Zhao , Juan-Carlos Algaba , Youngjoo Yun , Taehyun Jung , Do-Young Byun

Very long baseline radio interferometry (VLBI) with ground-based observatories is limited by the size of Earth, the geographic distribution of antennas, and the transparency of the atmosphere. In this whitepaper, we present Capella, a…

Instrumentation and Methods for Astrophysics · Physics 2024-06-28 Sascha Trippe , Taehyun Jung , Jung-Won Lee , Jan Wagner , Jeong-Yeol Han , Wonseok Kang , Jae-Hyun Kyeong , Junghwan Oh , Jae-Young Kim , Jongho Park , Jeffrey A. Hodgson

We observed the quadruple gravitationally lensed image of MGJ0414+0534 on 23 November 1997 with a global VLBI array at 8.4 GHz. We report wide-field imaging results of its four components at submilliarcsecond resolution, displaying complex…

Horizon-scale imaging with the Event Horizon Telescope (EHT) has provided transformative insights into supermassive black holes but its resolution and scope are limited by ground-based constraints such as the size of the Earth, its…

Instrumentation and Methods for Astrophysics · Physics 2024-12-04 Yassine Ben Zineb , Feryal Ozel , Dimitrios Psaltis

We present the results of the pilot observations of the Deep Extragalactic VLBI-Optical Survey (DEVOS). Our ultimate aim is to collect information on compact structures in a large sample of extragalactic radio sources (~10000 objects) up to…

Astrophysics · Physics 2009-11-13 L. Mosoni , S. Frey , L. I. Gurvits , M. A. Garrett , S. T. Garrington , Z. I. Tsvetanov

In this paper I outline a new strategy for the routine detection and imaging of faint (sub-mJy and microJy) radio sources with VLBI and SVLBI. The strategy relies on a combination of in-beam phase-referencing, wide-field VLBI imaging and…

Astrophysics · Physics 2007-05-23 M. A. Garrett

The space astrometry mission GAIA will construct a dense optical QSO-based celestial reference frame. For consistency between the optical and radio positions, it will be important to align the GAIA frame and the International Celestial…

Astrophysics · Physics 2009-11-13 Geraldine Bourda , Patrick Charlot , Richard Porcas , Simon Garrington

AIMS: We have found that the interferometric visibilities of VLTI-AMBER observations, extracted via the standard reduction package, are significantly biased when faint targets are concerned. The visibility biases derive from a time variable…

Astrophysics · Physics 2009-11-13 G. Li Causi , S. Antoniucci , E. Tatulli

We discuss possibilities and improvements which could be obtained, if a phased array with a large number (N=50-100) of sub-millimeter antennas - like the planned large southern array (the former LSA, now ALMA) is used for…

Astrophysics · Physics 2007-05-23 Thomas P. Krichbaum

Radio-loud active galactic nuclei (AGNs), hosting powerful relativistic jet outflows, provide an excellent laboratory for studying jet physics. Very long baseline interferometry (VLBI) enables high-resolution imaging on milli-arcsecond…

High Energy Astrophysical Phenomena · Physics 2018-02-07 X. -P. Cheng , T. An , X. -Y. Hong , J. Yang , P. Mohan , K. I. Kellermann , M. L. Lister , S. Frey , W. Zhao , Z. -L. Zhang , X. -C. Wu , X. -F. Li , Y. -K. Zhang

The Shanghai Astronomical Observatory (SHAO) of the Chinese Academy of Sciences (CAS) is studying a space VLBI (Very Long Baseline Interferometer) program. The ultimate objective of the program is to image the immediate vicinity of the…

Instrumentation and Methods for Astrophysics · Physics 2014-07-01 Xiaoyu Hong , Zhiqiang Shen , Tao An , Qinghui Liu , the Chinese Space VLBI Array team

Context: This is the first of a series of papers presenting VLBI observations of the 293 Caltech-Jodrell Bank Flat-Spectrum (hereafter CJF) sources and their analysis. Aims: One of the major goals of the CJF is to make a statistical study…

We report on the first VLBI image of the M81 nucleus (M81*) at a wavelength of 3.4 mm, obtained with the source-frequency phase-referencing (SFPR) technique. Thanks to the SFPR calibration, the coherent integration time could be eventually…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 Wu Jiang , Zhi-qiang Shen , Dong-rong Jiang , Ivan Marti-Vidal , Noriyuki Kawaguchi

This white paper describes the science case for Very Long Baseline Interferometry (VLBI) and provides suggestions towards upgrade paths for the European VLBI Network (EVN). The EVN is a distributed long-baseline radio interferometric array,…

It has been widely acknowledged that Very Long Baseline Interferometry (VLBI) in the submillimeter wavelengths can make imaging observations of super massive black holes possible. The Sub-Millimeter Array (SMA) along with the James Clerk…

Instrumentation and Methods for Astrophysics · Physics 2012-10-23 Vinayak Nagpal

In order to directly study the role of magnetic fields in the immediate vicinity of protostars, we use Very-Long-Baseline Interferometry (VLBI), aiming at the detection of non-thermal centimetric radio emission. This is technically the only…

Astrophysics · Physics 2009-11-13 Jan Forbrich , Maria Massi , Eduardo Ros , Andreas Brunthaler , Karl Menten

We observed the gravitationally lensed blazar JVAS B0218+357 with the KVN and VERA Array (KaVA) at 22, 43, and 86 GHz. The source has recently been identified as an active gamma-ray source up to GeV/TeV energy bands, rendering a unique…

Astrophysics of Galaxies · Physics 2020-09-03 Kazuhiro Hada , Kotaro Niinuma , Julian Sitarek , Cristiana Spingola , Ayumi Hirano

Many of the compact extragalactic radio sources that are used as fiducial points to define the celestial reference frame are known to have proper motions detectable with long-term geodetic/astrometric Very Long Baseline Interferometry…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-16 A. Moór , S. Frey , S. B. Lambert , O. Titov , J. Bakos