• Corpus ID: 20056522

Reconstructing Video from Interferometric Measurements of Time-Varying Sources

  title={Reconstructing Video from Interferometric Measurements of Time-Varying Sources},
  author={Katherine L. Bouman and Michael D. Johnson and Adrian V. Dalca and Andrew A. Chael and Freek Roelofs and Sheperd S. Doeleman and William T. Freeman},
Very long baseline interferometry (VLBI) makes it possible to recover images of astronomical sources with extremely high angular resolution. Most recently, the Event Horizon Telescope (EHT) has extended VLBI to short millimeter wavelengths with a goal of achieving angular resolution sufficient for imaging the event horizons of nearby supermassive black holes. VLBI provides measurements related to the underlying source image through a sparse set spatial frequencies. An image can then be… 

Principal Component Analysis as a Tool for Characterizing Black Hole Images and Variability

We explore the use of principal component analysis (PCA) to characterize high-fidelity simulations and interferometric observations of the millimeter emission that originates near the horizons of

Testing General Relativity with the Black Hole Shadow Size and Asymmetry of Sagittarius A*: Limitations from Interstellar Scattering

The Event Horizon Telescope, a global 230 GHz very-long-baseline interferometry array, achieves angular resolution of , sufficient to resolve the supermassive black hole Sagittarius A* (Sgr A*). This

Black Hole Spin Measurement Based on Time-domain VLBI Observations of Infalling Gas Clouds

The black hole spacetime is described by general relativity and characterized by two quantities: the black hole mass and spin. Black hole spin measurement requires information from the vicinity of

Testing general relativity with the Event Horizon Telescope

  • D. Psaltis
  • Physics
    General Relativity and Gravitation
  • 2019
The Event Horizon Telescope is a millimeter VLBI array that aims to take the first pictures of the black holes in the center of the Milky Way and of the M87 galaxy, with horizon scale resolution.

Image Reconstruction from Incomplete Frequency Information Using Yang Method

In many applications, an incomplete measurement case aims to obtain the desired original signal. However, the limited measured signal causes the predicted signal not to be the same as the original

The variable shadow of M87

Observing the dynamics of compact astrophysical objects provides insights into their inner workings and allows to probe physics under extreme conditions. The immediate vicinity of an active

On the prospects of imaging Sagittarius A* from space

Abstract Very Long Baseline Interferometry (VLBI) at sub-millimeter waves has the potential to image the shadow of the black hole in the Galactic Center, Sagittarius A* (Sgr A*), and thereby test



Dynamical Imaging with Interferometry

By linking widely separated radio dishes, the technique of very long baseline interferometry (VLBI) can greatly enhance angular resolution in radio astronomy. However, at any given moment, a VLBI

Computational Imaging for VLBI Image Reconstruction

This paper presents a novel Bayesian approach for VLBI image reconstruction, and shows that the method (CHIRP) produces good results under different settings such as low SNR or extended emission.

Deconvolution of VLBI images based on compressive sensing

  • A. B. Suksmono
  • Physics
    2009 International Conference on Electrical Engineering and Informatics
  • 2009
It is shown that CS is well-suited with the VLBI imaging problem and demonstrated that the proposed method is capable to reconstruct a simulated image of radio galaxy from its incomplete visibility samples taken from elliptical trajectories in the uv-plane.

Imaging the Schwarzschild-radius-scale Structure of M87 with the Event Horizon Telescope Using Sparse Modeling

We propose a new imaging technique for radio and optical/infrared interferometry. The proposed technique reconstructs the image from the visibility amplitude and closure phase, which are standard


Images of the linear polarizations of synchrotron radiation around active galactic nuclei (AGNs) highlight their projected magnetic field lines and provide key data for understanding the physics of

Superresolution Full-polarimetric Imaging for Radio Interferometry with Sparse Modeling

It is found that $\ell _1$+TV regularization can achieve much better image fidelity in linear polarization than other techniques over a wide range of spatial scales, not only in the super-resolution regime, but also on scales larger than the diffraction limit.


The black hole in the center of the Galaxy, associated with the compact source Sagittarius A* (Sgr A*), is predicted to cast a shadow upon the emission of the surrounding plasma flow, which encodes

Maximum Entropy Image Restoration in Astronomy

Imaging the two-dimensional intensity distribution of the sky has always been an important part of astronomy. This is particularly true at present, a time when aperture synthesis mapping is firmly

Sparse representations and convex optimization as tools for LOFAR radio interferometric imaging

The theory behind interferometric imaging, sparse representations and convex optimization, and their application with numerical tests with SASIR, an implementation of the FISTA, a Forward-Backward splitting algorithm hosted in a LOFAR imager are exposed.

Imaging an Event Horizon: submm-VLBI of a Super Massive Black Hole

A long standing goal in astrophysics is to directly observe the immediate environment of a black hole with angular resolution comparable to the event horizon. Realizing this goal would open a new