"interferometry"

Acceleration of the Sparse Modeling imaging tool for ALMA radio interferometric data

Sparse modeling is widely used in image processing, signal processing, and machine learning recently. Thanks to the research and progress in statistical mathematics along with the evolution of computational power, the technique is applicable to the …

New synthesis imaging tool for ALMA based on the sparse modeling

A new imaging tool for radio interferometry has been developed based on the sparse modeling approach. It has been implemented as a Python module operating on Common Astronomy Software Applications (CASA) so that the tool is able to process the data …

Super-resolution imaging of the protoplanetary disk HD 142527 using sparse modeling

High-resolution observations of protoplanetary disks with radio interferometers are crucial for understanding the planet formation process. Recent observations using Atacama Large Millimeter/submillimeter Array (ALMA) have revealed various …

Superresolution interferometric imaging with sparse modeling using total squared variation -- Application to imaging the black hole shadow

We propose a new imaging technique for interferometry using sparse modeling, utilizing two regularization terms: the $\ell_1$-norm and a new function named total squared variation (TSV) of the brightness distribution. First, we demonstrate that our …

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 data products of short-millimeter very long baseline …

Superresolution full-polarimetric imaging for radio interferometry with sparse modeling

We propose a new technique for radio interferometry to obtain superresolution full-polarization images in all four Stokes parameters using sparse modeling. The proposed technique reconstructs the image in each Stokes parameter from the corresponding …

PRECL: A new method for interferometry imaging from closure phase

For short-wavelength VLBI observations, it is difficult to measure the phase of the visibility function accurately. The closure phases are reliable measurements under this situation, though it is not sufficient to retrieve all of the phase …

Super-resolution imaging with radio interferometry using sparse modeling

We propose a new technique to obtain super-resolution images with radio interferometry using sparse modeling. In standard radio interferometry, sampling of $(u, v)$ is quite often incomplete and thus obtaining an image from observed visibilities …