GEMC Options

Option can be passed to gemc by command line and/or a gcard file (XML format).

Command Line Options

The syntax of the gemc command line options is:


For example, to set the primary particle momentum:

-BEAM_P="proton, 4.0*GeV, 20.0*deg, 10*deg"

Unless the argument is a single word, quotes are necessary.

Some options support multiple instances. For example, one could scale several fields with the SCALE_FIELD option:

-SCALE_FIELD="field1, 0.6"
-SCALE_FIELD="field2, -1"

Typing gemc -help will show the help sub-categories:

Help Options:

 >  -help-all:  all available options.
 >  -help-html:  write a formatted file options.html with the available gemc options.

  >  -help-control             control options.
  >  -help-fields              fields options.
  >  -help-general             general options.
  >  -help-generator           generator options.
  >  -help-luminosity          luminosity options.
  >  -help-materials           materials options.
  >  -help-mysql               mysql options.
  >  -help-output              output options.
  >  -help-physics             physics options.
  >  -help-transportation      transportation options.
  >  -help-verbosity           verbosity options.

You can access to a specific subcategory like this:

gemc -help-control


The syntax of the gcard options is:

<option name="OPTION"   value="argument"/>

For example, to set the primary particle momentum as above:

<option name="BEAM_P"   value="proton, 4.0*GeV, 20.0*deg, 10*deg"/>


All command line options can be used in the gcard and viceversa. The command line will superseed the gcard. When doing so, the option multiplicity is reset (i.e. if SCALE_FIELD is used in the gcard and the command line, only the command line option will be used.


All the options are saved in the output stream.

List of all the current GEMC options