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The Atacama Large Millimeter/submillimeter Array remains the largest mm radio interferometer observatory world-wide. It is now conducting its 11th observing cycle. In our previous paper presented at this conference series in 2020, we…

Instrumentation and Methods for Astrophysics · Physics 2024-08-09 Dirk Petry , María Díaz Trigo , Rüdiger Kneissl , Ignacio Toledo , Atsushi Miyazaki , Toshinobu Takagi , Ashley Barnes , Francesca Bonanomi

This manual is intended to help ALMA and other interferometer users improve images by recognising limitations and how to overcome them and deciding when and how to use self-calibration. The images provided by the ALMA Science Archive are…

Instrumentation and Methods for Astrophysics · Physics 2022-07-13 A. M. S. Richards , E. Moravec , S. Etoka , E. B. Fomalont , A. F. Pérez-Sánchez , M. C. Toribio , R. A. Laing

ALMA's high-resolution images allow to resolve the filamentary structure of the ISM down to few thousand au at kpc distances. We aim to systematically quantify the impact of the interferometric response and the effects of the short-spacing…

Astrophysics of Galaxies · Physics 2024-08-07 F. Bonanomi , A. Hacar , A. Socci , D. Petry , S. Suri

The Atacama Millimeter/submillimeter Array (ALMA) Phasing Project (APP) has developed and deployed the hardware and software necessary to coherently sum the signals of individual ALMA antennas and record the aggregate sum in Very Long…

An international consortium is presently constructing a beamformer for the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile that will be available as a facility instrument. The beamformer will aggregate the entire collecting…

Context: In recent years, stellar intensity interferometry has seen renewed interest from the astronomical community because it can be efficiently applied to Cherenkov telescope arrays. Aims: We have investigated the accuracy that can be…

Instrumentation and Methods for Astrophysics · Physics 2022-10-05 Michele Fiori , Giampiero Naletto , Luca Zampieri , Irene Jiménez Martínez , Carolin Wunderlich

Observations of the Sun at millimeter and submillimeter wavelengths offer a unique probe into the structure, dynamics, and heating of the chromosphere; the structure of sunspots; the formation and eruption of prominences and filaments; and…

The design of an interferometric array should allow optimal instrumental response regarding all possible source positions, times of integration and scientific goals. It should also take into account constraints such as forbidden regions on…

Astrophysics · Physics 2009-11-07 F. Boone

Magnetic Resonance Imaging (MRI) is a powerful technique employed for non-invasive in vivo visualization of internal structures. Sparsity is often deployed to accelerate the signal acquisition or overcome the presence of motion artifacts,…

Image and Video Processing · Electrical Eng. & Systems 2025-05-27 Gianluca Giacchi , Isidoros Iakovidis , Bastien Milani , Micah Murray , Benedetta Franceschiello

Radio telescope arrays are interferometers and thus require coherent capture and processing of the signal from the astronomical source being observed. In ALMA this is accomplished by using a clock at each antenna for down-conversion and…

Instrumentation and Methods for Astrophysics · Physics 2021-07-12 Brent Carlson

Heterodyne receivers register the sky signal on either a circular polarization basis (where it is split into left-hand and right-hand circular polarization) or a linear polarization basis (where it is split into horizontal and vertical…

Instrumentation and Methods for Astrophysics · Physics 2016-03-09 Ivan Marti-Vidal , Alan Roy , John Conway , Anton J. Zensus

Image quality in mosaicked observations from interferometric radio telescopes is strongly dependent on the accuracy with which the antenna primary beam is calibrated. The next generation of radio telescope arrays such as the Allen Telescope…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 Charles L. H. Hull , Geoffrey C. Bower , Steve Croft , Peter K. G. Williams , Casey Law , David Whysong

The Atacama Large Millimeter/submillimeter Array (ALMA) offers new diagnostic possibilities that complement other commonly used diagnostics for the study of our Sun. In particular, ALMA's ability to serve as an essentially linear…

Astronomers usually need the highest angular resolution possible, but the blurring effect of diffraction imposes a fundamental limit on the image quality from any single telescope. Interferometry allows light collected at widely-separated…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 John D. Monnier , Ronald J. Allen

The ALMACAL survey is based on a database of reprocessed ALMA calibration scans suitable for scientific analysis, observed as part of regular PI observations. We present all the data accumulated from the start of ALMA operations until May…

The Atacama Large millimeter/submillimeter Array (ALMA) obtains spatial resolutions of 15 to 5 milli-arcsecond (mas) at 275-950GHz (0.87-0.32mm) with 16km baselines. Calibration at higher-frequencies is challenging as ALMA sensitivity and…

Interferometric imaging now achieves angular resolutions as fine as 10 microarcsec, probing scales that are inaccessible to single telescopes. Traditional synthesis imaging methods require calibrated visibilities; however, interferometric…

Instrumentation and Methods for Astrophysics · Physics 2018-04-25 Andrew A. Chael , Michael D. Johnson , Katherine L. Bouman , Lindy L. Blackburn , Kazunori Akiyama , Ramesh Narayan

We reformulate the gain correction problem of the radio interferometry as an optimization problem with regularization, which is solved efficiently with an iterative algorithm. Combining this new method with our previously proposed imaging…

Instrumentation and Methods for Astrophysics · Physics 2024-12-05 Shiro Ikeda , Takeshi Nakazato , Takashi Tsukagoshi , Tsutomu T. Takeuchi , Masayuki Yamaguchi

Strong gravitational lensing acts as a cosmic telescope, enabling the study of the high-redshift universe. Astronomical interferometers, such as the Atacama Large Millimeter/submillimeter Array (ALMA), have provided high-resolution images…

Most statistical tools used to characterize the complex structures of the interstellar medium can be related to the power spectrum, and therefore to the Fourier amplitudes of the observed fields. To tap into the vast amount of information…

Astrophysics · Physics 2009-11-11 Francois Levrier , Edith Falgarone , Francois Viallefond
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