JEWEL relies heavily on PYTHIA 6 for the simulation of matrix elements, initial state parton showers and the hadronisation. It requires a slighlty modified version of PYTHIA 6.4.25, which is distributed together with JEWEL and is not an official release of PYTHIA and may not be used for anything else. Modifications with respect to the official PYTHIA version are (i) an enlarged event record which now has 23000 lines, (ii) a modified LHAPDF interface that can deal with nuclear PDF's and (iii) a customised version of PYEVWT that allows for the generation of weighted events.
The following paths need to be set for JEWEL to run:
To run JEWEL with the default setting no parameter file is needed: ./jewel-2.0.0-simple or ./jewel-2.0.0-vac Note, however, that also in the latter case nuclear PDF's will be used.
A parameter file can to be passed to change the setting: ./jewel-2.0.0-simple params.example.dat The file params.example.dat is included in the tarball as an example for a parameter file. The file can contain one parameter per line, the format is <name>␣<value>. Lines starting with a hash are comment lines. For a list of parameters and their default values please refer to the manual.