Tutorials for Very Long Baseline Interferometry
CASA is offering increased VLBI support through a collaboration with the Joint Institute for VLBI ERIC (JIVE). The below VLBI CASA tutorials introduce the CASA environment and touch upon the visualization, calibration and imaging capabilities available, along with the scripting methods so that you can create your own calibration scripts for your own data.
VLBI processing in CASA has been extensively tested with EVN and VLBA continuum data. Other use cases and telescopes are still being verified. Feedback on results (also successful ones) and missing or optimizing functionality is very welcome at casa_feedback_at_nrao.edu.
For the Event Horizon Telescope (EHT) project, one of three certified pipelines is based on CASA. This 'rPicard' pipeline has since evolved into a generic all-purpose pipeline for VLBI processing. While rPicard is not supported by the CASA team, users can find more information in this paper.
CASA tutorial: ENV Continuum Imaging & Calibration
CASA tutorial: EVN HI Spectral Line
Credits: These CASA tutorials represent publicly available materials developed by scientists from the University of Manchester, the Joint Institute for VLBI ERIC (JIVE), and the University of Pretoria/SARAO through funding from Development in Africa with Radio Astronomy (DARA). The materials are based upon a workshop developed by Anita Richards (University of Manchester) in 2016. The subsequent update has been conducted by Jack Radcliffe (SARAO/ University of Pretoria), which has been influenced by Des Small's (JIVE) EVN CASA tutorial, based on AIPS material provided by Minnie Mao. When starting with archival EVN observations, this EVN CASA tutorial explains the required steps for converting the data into a Measurement Set (in the EVN Continuum tutorial these steps are not complete). Thanks to Ilse van Bemmel (JIVE) for making these materials available for the CASA Guides.
While implementation of VLBI data processing is an ongoing effort in CASA, we also include below two AIPS tutorials on this topic.
AIPS tutorial: Simple Self-Calibration
AIPS tutorial: Spectral Lines and Astrometry