Skip to content
Go to file

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time


The Global Sky Model

The Global Sky Model (GSM) is generated from a database that contains all sources from the VLSS, TGSS, WENSS (main and polar) and NVSS survey catalogs. For the LOFAR calibration pipeline(s) these tools can be used to create a sky model catalog file in makesourcedb format. The gsm script extracts sources in a cone of a given radius around a given position on the sky from the Global Sky Model database, cross-matches these sources, fits the spectral index, curvature and higher-order terms. Then it writes the results to a plain text makesourcedb file, that can be used by other programs.

GSM Database

The GSM relies on the MonetDB database system. If you want to run it yourself you have to install it and get the catalog csv files from here. With the setup.db.batch script you can create the database, schema, tables, functions and load the data. Copy template_dbconfig.cfg somewhere to dbconfig.cfg and specify the database parameters. Note that you can also specify a remote GSM database. Provide it to the gsm script by setting the --dbconf relpath/to/dbconfig.cfg option. Default, it checks for the dbconfiguration file in the working directory.


The gsm-parameters configuration file needs to be copied from template_conf.cfg somewhere to config.cfg. Here you specify the parameters like central ra and dec, fov radius, etc. Default will look for the file in the working diectory. Otherwise it should be specified by the option --conf relpath/to/config.cfg.

The python wrapper script can be used to generate a Global Sky Model file in makesourcedb format and can be run as:

python [-h] [-d dbconfig.cfg] [-c config.cfg] [--version]

Note that since the last version we introduced the basecat argument. This can be set in the gsm-parameters config file to either VLSS or TGSS as the base catalogue for which counterparts will be searched in the other catalogues.

pip install gsm and run the gsm script

In your virtualenv you can pip install gsm and then simply use the bin/gsm script to run the GSM from the command line:

gsm [-d dbconfig] [-c config] [-v version] [-h help]


See the LOFAR Imaging Cookbook for more information.


Global Sky Model used for LOFAR imaging




No packages published