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Release of FastJet 3.5.1
(latest stable release), 1 July 2025 (release notes).
This is mainly a bug-fix release, with also some CMake build system improvements, notably Windows DLL support. See the full release notes for details.
This is mainly a bug-fix release, with also some CMake build system improvements, notably Windows DLL support. See the full release notes for details.
Latest stable release
of fjcore (v3.5.1), 1 July 2025.
Lightweight access to the core FastJet functionality (PseudoJet, JetDefinition, ClusterSequence and Selector).
It consists of just two files, fjcore.hh and fjcore.cc, which can easily be included in 3rd party projects. Compile time: a few seconds. A fortran interface and basic examples are also included in the distribution. Download size: 75k.
Lightweight access to the core FastJet functionality (PseudoJet, JetDefinition, ClusterSequence and Selector).
It consists of just two files, fjcore.hh and fjcore.cc, which can easily be included in 3rd party projects. Compile time: a few seconds. A fortran interface and basic examples are also included in the distribution. Download size: 75k.
Release of FastJet Contrib 1.102, 4 March 2026.
A package of contributed add-ons to FastJet. This release (see NEWS for details) updates QCDAwarePlugin to version 2.0.0. Fastjet contrib 1.100 and later requires FastJet 3.4.1 or higher and allows for dependencies between contribs. FastJet contrib 1.047 and later requires C++11 support in the compiler (if using GCC's g++ it should be version 5.1.0 or later). Direct download.
A package of contributed add-ons to FastJet. This release (see NEWS for details) updates QCDAwarePlugin to version 2.0.0. Fastjet contrib 1.100 and later requires FastJet 3.4.1 or higher and allows for dependencies between contribs. FastJet contrib 1.047 and later requires C++11 support in the compiler (if using GCC's g++ it should be version 5.1.0 or later). Direct download.