Stacking of large interferometric data sets in the image- and uv-domain - a comparative study
Journal article, 2015

We present a new algorithm for stacking radio interferometric data in the uv-domain. The performance of uv-stacking is compared to the stacking of fully imaged data using simulated Atacama Large Millimeter/submillimeter Array and the Karl G. Jansky Very Large Array (VLA) deep extragalactic surveys. We find that image-and uv-stacking produce similar results, however, uv-stacking is typically the more robust method. An advantage of the uv-stacking algorithm is the availability of uv-data post-stacking, which makes it possible to identify and remove problematic baselines. For deep VLA surveys uv-stacking yields a signal-to-noise ratio that is up to 20 per cent higher than image-stacking. Furthermore, we have investigated stacking of resolved sources with a simulated VLA data set where 1.5 arcsec (10-12 kpc at z similar to 1-4) sources are stacked. We find that uv-stacking, where a model is fitted directly to the visibilities, significantly improves the accuracy and robustness of the size estimates. While scientific motivation for this work is studying faint, high-z galaxies, the algorithm analysed here would also be applicable in other fields of astronomy. Stacking of radio interferometric data is also expected to play a big role for future surveys with telescopes such as Low-Frequency Array and Square Kilometre Array.

Radio-Emission

Vla-Cosmos Survey

Star-Formation

Submillimeter Properties

Deep Field-South

1.4 Ghz

Data Release

Lyman-Break Galaxies

Alma Survey

Author

Lukas Lindroos

Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics

Kirsten Kraiberg Knudsen

Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics

Wouter Vlemmings

Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics

John Conway

Chalmers, Earth and Space Sciences, Onsala Space Observatory

Ivan Marti-Vidal

Chalmers, Earth and Space Sciences, Onsala Space Observatory

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 446 4 3502-3515

Subject Categories

Astronomy, Astrophysics and Cosmology

Roots

Basic sciences

Infrastructure

Onsala Space Observatory

DOI

10.1093/mnras/stu2344

More information

Created

10/7/2017