SherpaFrag
Authors: Philip Ilten philip.james.ilten@cern.ch; Stephen Mrenna mrenna@fnal.gov; Christian T. Preuss preuss@uni-wuppertal.de
Description
This plugin provides an interface to Sherpa's cluster hadronization model. The color singlet system's produced by Pythia8 as input to the Lund fragmentation model are, instead, passed to Sherpa. The path to the pre-build Sherpa library (lib, include, etc) must be provided. Currently, instructions on how to install Sherpa are not provided. The current implementation was done for git branch rel-3-0-x on https://gitlab.com/sherpa-team/sherpa.git.
Authors
Philip Ilten philip.james.ilten@cern.ch; Stephen Mrenna mrenna@fnal.gov; Christian T. Preuss preuss@uni-wuppertal.de
Dependencies
This package is compatible with 8.316 and newer of Pythia8 and 3.0.0 and newer of Sherpa.
Configure and Build
This plugin must be configured with both Pythia8 and Sherpa.
./configure --with-pythia8=PYTHIA8_PATH --with-sherpa=SHERPA_PATH
Because the Sherpa configuration is non-standard it may be necessary to
set individual paths by hand:
--with-sherpa-include=SHERPA_BASE/<build-dir>/include/SHERPA-MC/
--with-sherpa-lib=SHERPA_BASE/<build-dir>/lib/SHERPA-MC/
A Docker container, pythia8/dev:sherpa, is also available which can be used to build and run this plugin, based on the hepstore/rivet container. The recipe for this container is defined with share/SherpaFrag/dev/sherpa.dev. The container can be run via singularity with the following command,
singularity shell docker://pythia8/dev:sherpa
or by docker with the following.
docker run -i -t -v "$PWD:$PWD" -w $PWD -u `id -u` --cap-add=SYS_PTRACE --rm pythia8/dev:sherpa bash --norc
When using this container, the configuration can be passed as follows.
./configure --with-pythia8=/hep/pythia/ --with-sherpa=/hep/sherpa/
After configuring, the plugin must be built.
make -j
Run
To run the plugin, navigate to the examples directory.
cd share/SherpaFrag/examples/
Then, make the run example.
make run
The run, with user supplied command files.
./run common.cmnd lepDijet.cmnd lepAnalyses.cmnd sherpaTune.cmnd
There are a number of command files provided.
- common.cmnd - configures the number of events to produce, whether to run RIVET analyses, and whether to run Sherpa fragmentation.
- lepAnalyses.cmnd - LEP RIVET analyses used for tuning.
- lepDijet.cmnd - produces LEP di-jet events.
- lhcDijet.cmnd - produces LHC di-jet events.
- pythiaTune.cmnd - relevant Pythia string parameters for tuning.
- sherpaTune.cmnd - relevant Sherpa cluster parameters for tuning.
Settings
There are a number of settings that can be passed to Pythia, defined by this plugin.
- SherpaFrag:settings - list of settings to pass to Sherpa, of the form {KEY1=VAL1,KEY2=VAL2,...}.
- SherpaFrag:outdir - output directory where Sherpa output is placed.