Version 1.4.2 is a convenience and bugfix release of Sherpa. The main new feature compared to 1.4.1 is the introduction of the TUNE parameter which can be set to NNPDF23, NNPDF23_UEup, NNPDF23_UEdown, CT10, CT10_UEup, and CT10_UEdown. The CT10 option is the default setting (no change to 1.4.1), NNPDF23 provides settings for NNPDF 2.3, and the UEup and UEdown variants change the underlying event activity by +/-10%.
Please see the Changelog below for a complete summary of the changes. If you would like to be informed about patches and newer releases, please subscribe to our announcement mailing list.
The Sherpa package can be downloaded here:
In can also be accessed via svn through
A Manual is included in the Manual/ directory of the tarball. It is available in the HTML and INFO format and provides extensive documentation of all parameters. It can also be found online.
The main reference describing the physics of Sherpa is JHEP02 (2009) 007. Please cite this publication if you have used Sherpa for your studies. Additionally, each run will produce a file called Sherpa_References.tex which contains information about the modules used in this run and the corresponding publications which should be referred. If in doubt, please seek the advice of the Sherpa authors.
You can find a large collection of example setups for using SHERPA in various different colliders/processes in the Examples/ directory of the tarball. They are also described in the manual.
Patches/known problems/known bugs/FAQs
All known problems/questions and their solutions can be found on our issue tracker (please log in with username "user" and password "sherpa"). If you encounter any problem while installing or running Sherpa, please open a new issue in the tracker.
- Bugfix for CA flavour sorting, cf. #242
- bugfix for NLO with universal selector
- New TUNE parameter