Year: 2022
Type: article
Abstract: New functionality to process Very Long Baseline Interferometry (VLBI) data has been implemented in the CASA package. This includes two new tasks to handle fringe fitting and VLBI-specific amplitude calibration steps. Existing tasks have been adjusted to handle VLBI visibility data and calibration meta-data properly. With these updates, it is now possible to process VLBI continuum and spectral line observations in CASA. This article describes the development and implementation, and presents an outline for the workflow when calibrating European VLBI Network or Very Long Baseline Array data in CASA. Though the CASA VLBI functionality has already been vetted extensively as part of the Event Horizon Telescope data processing, in this paper we compare results for the same data set processed in CASA and AIPS. We find identical results for the two packages and conclude that CASA in some cases performs better, though it cannot match AIPS for single-core processing time. The new functionality in CASA allows for easy development of pipelines or Jupyter notebooks, and thus contributes to raising VLBI data processing to present day standards for accessibility, reproducibility, and reusability.
Authors: Ilse M. van Bemmel, Mark Kettenis, Des Small, Michael Janssen, George A. Moellenbrock, Dirk Petry, Ciriaco Goddi, Justin D. Linford, Kazi L. J. Rygl, Elisabetta Liuzzo, Benito Marcote, Olga S. Bayandina, Neal Schweighart, Marjolein Verkouter, Aard Keimpema, Arpad Szomoru, Huib Jan van Langevelde
Institutions: Joint Institute for VLBI ERIC, Max Planck Institute for Radio Astronomy, National Radio Astronomy Observatory, European Southern Observatory, University of Cagliari, Osservatorio Astronomico di Cagliari, Istituto di Radioastronomia di Bologna, Arcetri Astrophysical Observatory, Leiden University, University of New Mexico, Leiden Observatory
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,850
OpenAlex ID: W4303439792