Common Astronomy Software Applications

CASA, the Common Astronomy Software Applications, is the primary data processing software for the Atacama Large Millimeter/submillimeter Array (ALMA) and Karl G. Jansky Very Large Array (VLA), and is often used also for other radio telescopes.

6.2.0/5.8.0 Release

CASA 6.2.0/5.8.0 can now be (downloaded) for general use. CASA 6.2.0 and 5.8.0 are scientifically equivalent, but CASA 6.2.0 is based on Python 3, while CASA 5.8.0 is the final version of the CASA 5 series that is based on Python 2. CASA 6.2.0 is available either as a downloadable tar-file, or through pip-wheel installation, which gives flexibility to integrate CASA into a customized Python environment.

New Features:

  • CASA 6: inclusion of remaining tasks, including interactive flagdata GUI

  • tclean: refactor of cube imaging (reliability, flexibility, peformance)

  • tclean: new option ‘briggsbwtaper’ and improved ‘briggs’ weighting

  • tclean: improved algorithm for fitting the PSF

  • tclean: updates to multiscale imaging to account for channel-dependence of the PSF

  • sdatmcor: new task for atmospheric correction of single dish data

  • sdbaseline: new parameters ‘updateweight’ and ‘sigmavalue’

  • accor: support of the new parameter ‘corrdepflags’

  • gencal: GAIN_CURVE subtable (caltype=’gc’) made available

  • plotms: improvements on avaraging, channel selection, and Mueller/Jones tables

  • simalma: updates to produce the expected output

  • listobs: extended output MS metadata

  • tec_maps: porting of ‘tec_maps’ script for ionospheric calibration in CASA 6

  • Consistency in error handling among tasks

  • Updates to the model for Mars.

  • Fixes to a number of bugs.

For more details on these and other new features, see the CASA 6.2.0 (Release Notes).

CASA is developed by an international consortium of scientists based at the National Radio Astronomical Observatory (NRAO), the European Southern Observatory (ESO), the National Astronomical Observatory of Japan (NAOJ), the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), CSIRO Astronomy and Space Science (CSIRO/CASS), and the Netherlands Institute for Radio Astronomy (ASTRON), under the guidance of NRAO.