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Related papers: Dynamical Imaging with Interferometry

200 papers

Space very long baseline interferometry (VLBI) has unique applications in high-resolution imaging of fine structure of astronomical objects and high-precision astrometry due to the key long space-Earth or space-space baselines beyond the…

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…

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

VLBI astrometry allows coordinates of celestial radio sources to be determined with submilliarcsecond accuracy. In particular, with differential VLBI astrometry, the standard errors of relative positions and proper motions can be as small…

Astrophysics · Physics 2007-05-23 Norbert Bartel

The application of Very Long Baseline Interferometry (VLBI) to the Search for Extraterrestrial Intelligence (SETI) has been limited to date, despite the technique offering many advantages over traditional single-dish SETI observations. In…

Understanding the variability of Sagittarius A* (Sgr A*) requires coordinated, multi-wavelength observations that span the electromagnetic spectrum. In this work, we focus on data from four key observatories: Chandra in the X-ray (2-8 keV),…

Instrumentation and Methods for Astrophysics · Physics 2026-01-29 Gabriel Sasseville , Julie Hlavacek-Larrondo , Daryl Haggard , Alexandre Adam , Hadrien Paugnat , Gunther Witzel

Very Long Baseline Atom Interferometry (VLBAI) corresponds to ground-based atomic matter-wave interferometry on large scales in space and time, letting the atomic wave functions interfere after free evolution times of several seconds or…

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

The high angular resolution and sensitivity of Very Long Baseline Interferometry (VLBI) offer a unique tool to identify and study active galactic nuclei and star-formation activity over cosmic time. However, despite recent technical…

Astrophysics of Galaxies · Physics 2024-12-05 Célestin Herbé-George , J. P. Mckean , Raffaella Morganti , Jack F. Radcliffe

Sagittarius A* (Sgr A*) is the variable radio, near-infrared (NIR), and X-ray source associated with accretion onto the Galactic center black hole. We have analyzed a comprehensive submillimeter (including new observations simultaneous with…

Intensity interferometry is a technique developed many decades ago, that has recently enjoyed a renaissance thanks in part to advances in photodetector technology. We investigate the potential for long-baseline optical intensity…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 Neal Dalal , Marios Galanis , Charles Gammie , Samuel E. Gralla , Norman Murray

Within the last 10 years, long-baseline optical interferometry (LBOI) has benefited significantly from increased sensitivity, spatial resolution, and spectral resolution, e.g., measuring the diameters and asymmetries of single stars,…

Because of atmospheric turbulence, obtaining high angular resolution images with a high dynamic range is difficult even in the near infrared domain of wavelengths. We propose a novel technique to overcome this issue. The fundamental idea is…

Astrophysics · Physics 2009-11-11 G. Perrin , S. Lacour , J. Woillez , E. Thiebaut

The new technique, multi-frequency imaging (MFI) is developed. In VLBI, Multi-Frequency Imaging (MFI) consists of multi-frequency synthesis (MFS) and multi-frequency analysis (MFA) of the VLBI data obtained from observations on various…

Astrophysics · Physics 2007-05-23 S. Likhachev

Very long baseline interferometry (VLBI) astrometry is used to determine the three-dimensional position and proper motion of astronomical objects. A typical VLBI astrometric campaign generally includes around ten observations, making it…

High Energy Astrophysical Phenomena · Physics 2025-07-30 Ashish Kumar , Adam T. Deller , Pankaj Jain , Javier Moldón

The ngVLA is a new interferometric radio astronomy facility with transformative capabilities, being developed by the National Radio Astronomy Observatory. It combines two orders of magnitude in frequency coverage, over 1.2 - 116 GHz, with…

Instrumentation and Methods for Astrophysics · Physics 2025-04-22 T. K. Sridharan , S. Bhatnagar , P. Jagannathan , K. Golap

We present the first event-horizon-scale images and spatiotemporal analysis of Sgr A* taken with the Event Horizon Telescope in 2017 April at a wavelength of 1.3 mm. Imaging of Sgr A* has been conducted through surveys over a wide range of…

High Energy Astrophysical Phenomena · Physics 2023-11-17 The Event Horizon Telescope Collaboration

A space-based very long baseline interferometry (VLBI) programme, named as the Cosmic Microscope, is proposed to involve dual VLBI telescopes in the space working together with giant ground-based telescopes (e.g., Square Kilometre Array,…

Instrumentation and Methods for Astrophysics · Physics 2022-05-19 Tao An , Sumit Jaiswal , Prashanth Mohan , Zhen Zhao , Baoqiang Lao