CASA, the Common Astronomy Software Applications for Radio Astronomy

TLDR

CASA is the primary data‑processing software for ALMA and VLA, also used for other radio telescopes, and it handles data from single‑dish, aperture‑synthesis, and VLBI instruments while supporting calibration and imaging pipelines for ALMA, VLA, VLASS, and the Nobeyama 45 m telescope. The paper provides a high‑level overview of CASA’s structure and outlines procedures for calibrating and imaging radio data within the software. CASA is developed by an international consortium of scientists and engineers from NRAO, ESO, NAOJ, and JIV‑ERIC under NRAO guidance.

Abstract

CASA, the Common Astronomy Software Applications, is the primary data processing software for the Atacama Large Millimeter/submillimeter Array (ALMA) and the Karl G. Jansky Very Large Array (VLA), and is frequently used also for other radio telescopes. The CASA software can handle data from single-dish, aperture-synthesis, and Very Long Baseline Interferometery (VLBI) telescopes. One of its core functionalities is to support the calibration and imaging pipelines for ALMA, VLA, VLA Sky Survey (VLASS), and the Nobeyama 45m telescope. This paper presents a high-level overview of the basic structure of the CASA software, as well as procedures for calibrating and imaging astronomical radio data in CASA. CASA is being developed by an international consortium of scientists and software engineers based at the National Radio Astronomical Observatory (NRAO), the European Southern Observatory (ESO), the National Astronomical Observatory of Japan (NAOJ), and the Joint Institute for VLBI European Research Infrastructure Consortium (JIV-ERIC), under the guidance of NRAO.