WSClean version 2.4

Released 2017-05-28

Summary: Version 2.4 mostly contains small improvements on various points. Improved source component output allows better integration with (DD and DI) self-calibration pipelines, and continued work on the integration with IDG is aiming towards a fast, full A-correction imager.

New features:

  • Option -save-source-list to save a component list including Gaussians for multi-scale components. The output format is supported by DPPP. Old option -save-component-list has been removed.

  • Source lists can be primary-beam corrected by combining -save-source-list with -apply-primary-beam (SF #111).

  • Added keywords TELESCOP, OBSERVER and OBJECT to fits output (SF #112).

  • Fitting a Gaussian to the PSF is now more stable, and deals better with border cases (reported by G . Heald).

  • Multi-frequency cleaning will now properly take channel weights into account during spectral fitting and peak finding (SF #109)

  • Flux density values are now reported with sensible units, and units can be given on the cmdline (SF #104).

  • WSClean will by default now stop deconvolution after 20 major iterations, which can be changed with the new option -nmiter (SF #117, requested by N. Hurley Walker).

  • Option -save-psf-pb to be able to get a corrected PSF.

  • Option -circularbeam now properly performs a constrained fit (SF #55).

  • Option -multiscale-convolution-padding to change the default padding.

  • WSClean now reports the reason for stopping cleaning.

  • Slight increase of gridding speed, because X and Y dimensions of gridding kernel are now stored separately. Larger oversampling rates are now also supported.

Bugfixes:

  • Parameter -stopnegative was ignored since the new generalized cleaning algorithm was implemented (reported by N. Hurley-Walker and C. Tremblay).

  • In multi-scale, joined polarizations mode, WSClean could not determine scale sizes when last channel has no unflagged visibilities (Reported by R. van Weeren).

  • In joined polarization mode, WSClean could continuously perform further major iterations without improving the residuals any further (reported by N. Hurley-Walker).

  • Deprecated parameter name -rms-background, which was renamed to -local-rms.

  • Fixes for IDG gridding; CPU and GPU gridding & cleaning with IDG works.

  • Version information now includes availability of IDG.

  • More unit tests.

  • Support proper displaying of negative angles.

  • Refactoring of primary beam correction code.