Rapthor: LOFAR DDE Pipeline

Rapthor is an experimental pipeline for correcting direction-dependent effects in LOFAR data. It is also being developed for use on SKA-Low data. It uses DP3 and WSClean to derive and apply the corrections in facets or as smooth 2-D screens. It uses CWL for the pipeline language and either Toil or StreamFlow to run the pipelines.

Documentation

Extensive documentation can be found on Read the Docs.

Installation

To install rapthor, follow the instructions below.

If you are using the SKAO AWS cluster, follow the instructions here.

Dependencies

Rapthor requires the following packages (beyond those installed automatically with rapthor):

• DP3 (version 6.3 or later; building with AOFlagger, EveryBeam, and IDG is required)
• EveryBeam (version 0.7.1 or later)
• IDG (version 1.2.0 or later)
• WSClean (version 3.4 or later; building with EveryBeam and IDG is required)

It is strongly recommended to also build the following packages from source, because the version that can be installed from the Linux distribution is usually too old:

• AOFlagger (version 3.4.0 or later)
• Casacore (version 3.7.1 or later)
• Python-Casacore (version 3.7.1 or later)

Downloading and Installing

Installation can be done in a number of ways. In order of preference (read: ease of use):

1. Install the latest release from PyPI:

   pip install rapthor
   

2. Install directly from the Rapthor git repository. This option is useful if you want to use one or more features that have not yet been released:

   pip install --upgrade pip
   pip install git+https://git.astron.nl/RD/rapthor.git[@<branch|tag|hash>]
   

   If the optional @<branch|tag|hash> is omitted, HEAD of the master branch will used.

3. Clone the git repository, and install from your working copy. This option is mostly used by developers who want to make local changes:

   pip install --upgrade pip
   git clone https://git.astron.nl/RD/rapthor.git
   cd rapthor
   git checkout [<branch|tag|hash>]  #optionally
   pip install .
   

Note

When installing Rapthor from source (options 2 and 3), you will need pip version 23 or later. That is why you need to upgrade to the latest version of pip before you install from source.

Usage

The rapthor executable can be used from the command line with a parset that defines the parameters of the run. E.g.:

$ rapthor rapthor.parset

The parset defines the input and working directories, various options, etc. For details, please see the example parset in the examples directory.