Physics eXtension Library (PXL)


Get a quick start with the code examples in pxlexample.cc, the PXL Fast Navigator and a complete overview in the PXL Namespace Reference.


The Physics eXtension Library (PXL) is a C++ class collection for fourvector analysis and hypothesis evolution in advanced High Energy Physics (HEP) analysis. The PXL is based on the ANSI C++ language standard with Standard Template Library (STL) and the ZLIB Data Compression Library.

PXL provides a general, persistent container model for complete HEP events. Event information and reconstructed objects can be stored by deploying PXL generalized objects such as particles, vertices, events and collisions. In the analysis of an event containing reconstructed data, new information can be added to each object by means of user event data. PXL provides the relation management necessary for building up decay trees in high-luminosity events with multiple collisions. It also provides classes for multi-process analysis and hypothesis evolution for processes with ambiguous event topologies. Hypothesis evolution performance is optimized by making use of a smart copy-on-write mechanism minimizing CPU and memory usage.

PXL can be used stand-alone as well as within arbitrary experiment specific C++ software frameworks. A dedicated PXL extension for the CMS experiment at CERN can be used. PXL "skins" for other experiments (e.g. for future ILC experiment) are under development.


The Python PXL manual gives information on the Python extension of PXL.
The PXL Namespace Reference gives a complete overview of all classes and typedefs.
The PXL Fast Navigator provides quick access to the most relevant classes and typedefs of:

Current Leading Authors

Andreas Hinzmann (a,b), Gero Mueller (a), Jan Steggemann (a,b), Tobias Winchen (a)

Current Advisors

Martin Erdmann (a,b)


(a) RWTH Aachen University, Physics Institute 3A, Physikzentrum, D-52056 Aachen, Germany
(b) CERN - European Organization for Nuclear Research, CH-1211 Geneva 23, Switzerland


The authors would like to thank Ulrich Felzmann, Carsten Hof, Clemens Zeidler, Philipp Biallass, Matthias Kirsch, Alexander Schmidt, Joanna Weng for helpful contributions and feedback. Special thanks to the former project leader and leading author Steffen Kappler and to the former leading author Christophe Saout. This project is supported by Bundesministerium fuer Bildung und Forschung (Berlin/Germany) and Deutsche Forschungsgemeinschaft (Bonn/Germany).


Physics eXtension Library (PXL)

C++ Toolkit for Fourvector Analysis, Relation Management and Hypothesis Evolution in High Energy Physics

Copyright (C) 2006-2015 Martin Erdmann -

E-mail contact: vispa.nosp@m.@lis.nosp@m.ts.rw.nosp@m.th-a.nosp@m.achen.nosp@m..de
Website: http://vispa.physik.rwth-aachen.de

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU LESSER GENERAL PUBLIC LICENSE (Version 2.1, February 1999) for more details.