VINCIA User Reference

March 2011 © W. T. Giele, D. A. Kosower, M. Ritzmann, P. Z. Skands

The VINCIA code is a plugin to the high-energy physics event generator PYTHIA 8. It is based on the dipole-antenna picture of QCD and focusses on describing quark and gluon radiation with high precision. It incorporates a novel scheme for matching to fixed-order matrix elements and also has extensive possibilities for estimating the remaining uncertainties by systematic variation of shower parameters. When activated, it replaces the internal PYTHIA parton cascades. Hadronization is performed as usual in PYTHIA, with the Lund string fragmentation model. VINCIA is currently implemented for QCD final-state showers and includes mass effects for charm and heavier quarks.

This documentation contains brief descriptions of each of the user-specifiable parameters of the VINCIA code, together with instructions how to install, link, and initialize it. Use the menu to the left to navigate. These files are purely for documentation and should not be modified by the user. Instead, see the section on Initialization for how to set and change parameters.

To ensure accurate reproducibility, when quoting VINCIA results, please state both the exact PYTHIA and VINCIA versions used, along with any relevant non-default settings (for both programs). On plots, please give both PYTHIA and VINCIA versions.

VINCIA is licenced under the GNU GPL version 2. Please respect the MCnet Guidelines for Event Generator Authors and Users. The name VINCIA stands for "Virtual Numerical Collider with Interleaved Antennae".

Compatibility

Use the following compatibility table to ensure that your VINCIA and PYTHIA versions are compatible

PYTHIA Versions VINCIA Versions Comments

8.145 1.025 PYTHIA changed CoupSM to Couplings
8.135 - 8.140 1.024 PYTHIA modified inherited TimeShower::prepare() function
8.135 1.019 - 1.023 PYTHIA removed static dependencies
8.100 - 8.130 1.000 - 1.018

Types of Parameters

As in PYTHIA 8, there are 4 types of parameters:

Useful References

A log of update notes and installation instructions is kept in the README.TXT accompanying the distribution.

The main VINCIA references are: The main PYTHIA 8 reference is

The interface to MADGRAPH further relies on To learn more about the physics of Event Generators, see The default antenna functions used by VINCIA are described in detail in The basic use of dipole-antennae as a dual description of QCD in the context of Shower Monte Carlos goes back to the Lund dipole, To learn more about Les Houches color tags, used both by PYTHIA and VINCIA to keep track of color connections, see

Version

These settings should not be changed by the ordinary user, but appear here for documentation purposes, and so that they can form part of the standard databases and be queried accordingly.

parm  Vincia:versionNumber   (default = 1.025)
Version and subversion number, with three significant decimals.

mode  Vincia:versionDate   (default = 20110318)
Last date of change of current (sub)version, in format yyyymmdd.

Last modified: