Using the pipeline script¶

WARNING: take care when running more than one instance of the imaging pipeline on the same system, as they can interfere with each other on certain stages; for example, the astrometry-related stages.

When the craft-optical-followup package has been properly installed (see Installation), the script craft_optical_followup will be placed in the bin directory for the current environment, and thus should be callable from anywhere.

$ craft_optical_followup

Simply invoking this from your terminal will conjure an interactive programme via which any of the supported pipelines can be launched, and guiding you through the main options, such as which Field and Epoch you want to work on. However, some of these can be skipped by including parameter flags:

$ craft_optical_followup --epoch FRB20180924_FORS2_1 --field FRB20180924

A full listing of valid flags is given below.

So long as an Epoch has been generated previously, the --field argument is redundant; the pipeline remembers which field an epoch belongs to.

New Epochs¶

If, however, it has not, the window will request further input. For the most part these questions are self-explanatory, and will ask you to specify the mode (spectroscopy or imaging; currently only imaging has any meaningful functionality) and the instrument on which the Epoch was observed. If the field is also new, you will need to provide some other information such as position on the sky.

A new .yaml will be generated in the main parameter directory <param_dir>/fields/<field>/<mode>/<instrument>/<epoch_name>.yaml, containing the information you’ve given. The config file for the Field it belongs to can also be found under <param_dir>/fields/<field>/<mode>/<instrument>/<epoch_name>.yaml,

For more detailed control–for example, to skip or modify pipeline steps (as may be necessary for unusual fields, eg if the astrometry stage is having trouble converging on a solution with the default settings)–the configuration YAML file for the Epoch or for its Field can be edited. For more on this file, see Configuration files.

Script parameters¶

A description of these flags and parameters can be displayed by invoking:

$ craft_optical_pipeline -h