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.
Run gsm.py
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 gsm.py 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 gsm.py can be used to generate a
Global Sky Model file
in makesourcedb format and can be run as:
python gsm.py [-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]
Documentation
See the LOFAR Imaging Cookbook for more information.
